fix(protocol): align quality ack schema

fix(protocol): fence gateway work recovery
feat(protocol): freeze M4 native session RC6 contract
2026-08-13 07:53:35 +07:00 · 2026-08-13 07:43:42 +07:00 · 2026-08-13 07:18:03 +07:00
43 changed files with 5819 additions and 488 deletions
@@ -9,9 +9,12 @@ valid-controller	1	gateway_input	hex=5647493105110200030004ffff00010002000300040
 valid-controller-release	1	gateway_input	hex=5647493105110200000000000000000000000000000000	valid
 valid-absolute-mouse	1	gateway_input	hex=56474931060804d202370a0005a0	valid
 valid-scroll	1	gateway_input	hex=564749310704ff880078	valid
+valid-controller-arrival	1	gateway_input	hex=564749310808020003010000001f	valid
 valid-idr	1	gateway_feedback	hex=5647463100010000	valid
 valid-fec	1	gateway_feedback	hex=56474631000200150000002a000500030002000a000200080002140001	valid
 valid-terminal-receipt	1	gateway_feedback	hex=5647463100030000	valid
+valid-quality-prompt	1	gateway_feedback	hex=564746310004001812345678123456781234567812345678000000000000002a	valid
+valid-stop-prompt	1	gateway_feedback	hex=564746310005001012345678123456781234567812345678	valid
 valid-termination	1	gateway_feedback	hex=564746310110000400000001	valid
 valid-rumble	1	gateway_feedback	hex=56474631011100050112345678	valid
 valid-hdr	1	gateway_feedback	hex=564746310112000101	valid
@@ -30,5 +33,9 @@ invalid-terminal-receipt-direction	1	gateway_feedback	hex=5647463101030000	inval
 invalid-terminal-receipt-body	1	gateway_feedback	hex=5647463100030001ff	invalid:length
 invalid-terminal-receipt-truncated	1	gateway_feedback	hex=56474631000300	invalid:truncated
 invalid-terminal-receipt-length	1	gateway_feedback	hex=5647463100030001	invalid:length
-invalid-feedback-type	1	gateway_feedback	hex=5647463100040000	invalid:type
+invalid-feedback-type	1	gateway_feedback	hex=5647463100060000	invalid:type
+invalid-quality-prompt-trailing	1	gateway_feedback	hex=564746310004001912345678123456781234567812345678000000000000002a00	invalid:length
+invalid-quality-prompt-zero-uuid	1	gateway_feedback	hex=564746310004001800000000000000000000000000000000000000000000002a	invalid:field
+invalid-stop-prompt-zero-uuid	1	gateway_feedback	hex=564746310005001000000000000000000000000000000000	invalid:field
+invalid-controller-arrival-family	1	gateway_input	hex=564749310808020003040000001f	invalid:field
 invalid-feedback-length	1	gateway_feedback	hex=5647463101100003000000	invalid:length
@@ -0,0 +1 @@
+{"mode":"auto","target_kbps":1000}
@@ -0,0 +1 @@
+{"transport":"quic-tls13","framing":"datagram-v2","media":"encoded","audio":"encoded","source_rate_control":"server","client_decode":["h264-opus"]}
@@ -0,0 +1 @@
+{"version":"1","session_id":"session-1","gateway_id":"gateway-1","reconnect_sequence":2,"operation_id":"12345678-1234-1234-1234-123456789abc","revision":7,"lease_generation":3,"outcome":"applied","current_applied_revision":6}
@@ -0,0 +1 @@
+{"version":"1","session_id":"session-1","gateway_id":"gateway-1","reconnect_sequence":2,"operation_id":"12345678-1234-1234-1234-123456789ABC","revision":7,"lease_generation":3,"outcome":"unknown"}
@@ -0,0 +1 @@
+{"version":"1","session_id":"session-1","gateway_id":"gateway-1","reconnect_sequence":2,"operation_id":"00000000-0000-0000-0000-000000000000","revision":7,"lease_generation":3,"outcome":"unknown"}
@@ -0,0 +1 @@
+{"version":"1","session_id":"session-1","gateway_id":"gateway-1","reconnect_sequence":2,"acquisition":"poll","operation_id":"12345678-1234-1234-1234-123456789abc","revision":7}
@@ -26,5 +26,14 @@
    "audience": "versevdi-gateway"
  },
  "correlation_id": "correlation-1",
-  "provider_url": "https://provider.invalid"
+  "provider_url": "https://provider.invalid",
+  "selected_descriptor": {
+    "video_profile": {"codec": "h264", "bit_depth": 8, "chroma_subsampling": "4:2:0", "color_space": "bt709-limited", "transfer_function": "sdr"},
+    "audio_profile": {"codec": "opus", "sample_rate_hz": 48000, "channels": 2, "channel_layout": "stereo", "packet_duration_ms": 5},
+    "display_mode": {"resolution_width": 1920, "resolution_height": 1080, "fps": 60},
+    "bitrate_target_kbps": 20000,
+    "bitrate_maximum_kbps": 40000,
+    "adjustment": {"display_reason": "none", "bitrate_reason": "none"},
+    "media_timestamp_basis": "gateway-send-wall-clock-ms"
+  }
 }
@@ -0,0 +1 @@
+{"resolution_width":1920,"resolution_height":1080,"fps":60,"codec":"H264","bitrate_kbps":20000,"audio_enabled":true}
@@ -0,0 +1 @@
+{"operation_id":"12345678-1234-1234-1234-123456789abc","session_id":"session-1","revision":7,"state":"pending","requested_bitrate_preference":{"mode":"auto"},"effective_bitrate_kbps":20000,"governing_policy_version":"policy-1","session_version":2,"created_at":"2099-01-01T00:00:00.100Z","deadline_at":"2099-01-01T00:00:30Z","updated_at":"2099-01-01T00:00:00Z"}
@@ -0,0 +1 @@
+{"operation_id":"12345678-1234-1234-1234-123456789abc","session_id":"session-1","revision":7,"state":"pending","requested_bitrate_preference":{"mode":"auto"},"effective_bitrate_kbps":20000,"governing_policy_version":"policy-1","session_version":2,"created_at":"2099-01-01T00:00:00+00:00","deadline_at":"2099-01-01T00:00:30Z","updated_at":"2099-01-01T00:00:00Z"}
@@ -0,0 +1 @@
+{"video_profile":{"codec":"h264","bit_depth":8,"chroma_subsampling":"4:2:0","color_space":"bt709-limited","transfer_function":"sdr"},"audio_profile":{"codec":"opus","sample_rate_hz":48000,"channels":2,"channel_layout":"stereo","packet_duration_ms":5},"display_mode":{"resolution_width":1920,"resolution_height":1080,"fps":60},"bitrate_target_kbps":20000,"bitrate_maximum_kbps":40000,"adjustment":{"display_reason":"none","bitrate_reason":"none"},"media_timestamp_basis":"gateway-send-wall-clock-ms","provider_identity":"forbidden"}
@@ -0,0 +1 @@
+{"client_device_id":"device-1","device_key_id":"key-1","pool_id":"pool-1","idempotency_key":"request-1"}
@@ -0,0 +1 @@
+{"codec":"vp9","bit_depth":8,"chroma_subsampling":"4:2:0","color_space":"bt709-limited","transfer_function":"sdr"}
@@ -11,5 +11,34 @@
    "fixtures/conformance/gateway-input-feedback-v1.tsv",
    "fixtures/conformance/tunnel-v1.tsv"
  ],
-  "corpus_sha256": "6d2ce3a855b2fa45733a5f7b5b4c2e68448cceed5dfbca535ec81fe8cf230b30"
+  "corpus_sha256": "10751a9192961aeb8ddcf3bbf720b026b07f92c871c813c301660dd3de930186",
+  "json_files": [
+    "fixtures/invalid/authenticated-session-partial-native-identity.json",
+    "fixtures/invalid/bitrate-preference-auto-target.json",
+    "fixtures/invalid/browser-session-native-identity.json",
+    "fixtures/invalid/capability-rc5-opaque.json",
+    "fixtures/invalid/gateway-quality-ack-contradictory.json",
+    "fixtures/invalid/gateway-quality-ack-uppercase-uuid.json",
+    "fixtures/invalid/gateway-quality-ack-zero-uuid.json",
+    "fixtures/invalid/gateway-quality-poll-coordinates.json",
+    "fixtures/invalid/manifest-provider-field.json",
+    "fixtures/invalid/native-session-missing-identity.json",
+    "fixtures/invalid/provider-stream-policy-rc5.json",
+    "fixtures/invalid/quality-operation-noncanonical-fraction.json",
+    "fixtures/invalid/quality-operation-offset-time.json",
+    "fixtures/invalid/selected-session-descriptor-provider-field.json",
+    "fixtures/invalid/session-request-policy-snapshot.json",
+    "fixtures/invalid/session-request-rc5.json",
+    "fixtures/invalid/video-profile-unknown.json",
+    "fixtures/valid/authenticated-browser-session.json",
+    "fixtures/valid/authenticated-native-session.json",
+    "fixtures/valid/gateway-quality-ack-applied.json",
+    "fixtures/valid/gateway-quality-poll.json",
+    "fixtures/valid/manifest.json",
+    "fixtures/valid/native-tunnel-credential.json",
+    "fixtures/valid/selected-session-descriptor.json",
+    "fixtures/valid/session-quality-limits.json",
+    "fixtures/valid/session-request.json"
+  ],
+  "json_corpus_sha256": "08dea278526a523d21ea4ca6270ba1e33d44dc0d701681917d7ffc6fb13053d7"
 }
@@ -0,0 +1 @@
+{"version":"1","session_id":"session-1","gateway_id":"gateway-1","reconnect_sequence":2,"operation_id":"12345678-1234-1234-1234-123456789abc","revision":7,"lease_generation":3,"outcome":"applied","current_applied_revision":7}
@@ -0,0 +1 @@
+{"version":"1","session_id":"session-1","gateway_id":"gateway-1","reconnect_sequence":2,"acquisition":"poll"}
@@ -25,5 +25,14 @@
    "expires_at": "2099-01-01T00:00:00Z",
    "audience": "versevdi-gateway"
  },
-  "correlation_id": "correlation-1"
+  "correlation_id": "correlation-1",
+  "selected_descriptor": {
+    "video_profile": {"codec": "h264", "bit_depth": 8, "chroma_subsampling": "4:2:0", "color_space": "bt709-limited", "transfer_function": "sdr"},
+    "audio_profile": {"codec": "opus", "sample_rate_hz": 48000, "channels": 2, "channel_layout": "stereo", "packet_duration_ms": 5},
+    "display_mode": {"resolution_width": 1920, "resolution_height": 1080, "fps": 60},
+    "bitrate_target_kbps": 20000,
+    "bitrate_maximum_kbps": 40000,
+    "adjustment": {"display_reason": "none", "bitrate_reason": "none"},
+    "media_timestamp_basis": "gateway-send-wall-clock-ms"
+  }
 }
@@ -0,0 +1,9 @@
+{
+  "video_profile": {"codec": "hevc", "bit_depth": 8, "chroma_subsampling": "4:2:0", "color_space": "bt709-limited", "transfer_function": "sdr"},
+  "audio_profile": {"codec": "opus", "sample_rate_hz": 48000, "channels": 2, "channel_layout": "stereo", "packet_duration_ms": 5},
+  "display_mode": {"resolution_width": 2560, "resolution_height": 1440, "fps": 120},
+  "bitrate_target_kbps": 40000,
+  "bitrate_maximum_kbps": 50000,
+  "adjustment": {"display_reason": "none", "bitrate_reason": "policy_default"},
+  "media_timestamp_basis": "gateway-send-wall-clock-ms"
+}
@@ -0,0 +1,9 @@
+{
+  "policy_version_id": "policy-1",
+  "policy_display_limit": {"resolution_width": 3840, "resolution_height": 2160, "fps": 120},
+  "selectable_display_maximum": {"resolution_width": 3840, "resolution_height": 2160, "fps": 120},
+  "display_limit_override": false,
+  "bitrate_minimum_kbps": 1000,
+  "bitrate_target_kbps": 20000,
+  "bitrate_maximum_kbps": 50000
+}
@@ -2,5 +2,9 @@
  "client_device_id": "device-1",
  "device_key_id": "key-1",
  "pool_id": "pool-1",
-  "idempotency_key": "request-1"
+  "idempotency_key": "request-1",
+  "video_profiles": [
+    {"codec": "h264", "bit_depth": 8, "chroma_subsampling": "4:2:0", "color_space": "bt709-limited", "transfer_function": "sdr"}
+  ],
+  "bitrate_preference": {"mode": "auto"}
 }
@@ -36,6 +36,7 @@ during cleanup.
 | `0x05` | controller state | `controller` (0 through 15), `active_mask` (u16), `button_flags` (u16), `left_trigger` (u8), `right_trigger` (u8), `left_x` (i16), `left_y` (i16), `right_x` (i16), `right_y` (i16), `extra_button_flags` (u16). A zero `active_mask` and zero state is release. |
 | `0x06` | absolute mouse | `x` (u16), `y` (u16), `viewport_width` (u16), `viewport_height` (u16). Viewport dimensions must be nonzero and each coordinate must be strictly smaller than its corresponding dimension. |
 | `0x07` | high-resolution scroll | `vertical_delta` (i16), `horizontal_delta` (i16). Positive and negative values preserve the client scroll direction without provider-specific scaling. |
+| `0x08` | controller arrival | `controller` (u8, 0 through 15), `active_mask` (u16), `family` (u8: `0` unknown, `1` xbox, `2` playstation, `3` nintendo), `supported_button_flags` (u32). It must precede controller state for that controller. |

 Keyboard, mouse button, UTF-8, controller, absolute mouse, and scroll messages
 are delivered over the gateway's reliable ordered input flow. Relative and
@@ -60,7 +61,12 @@ is the following exact envelope:
 | 8 | N | payload | exact type-specific body |

 The client-to-gateway types are `0x01` IDR request (empty), `0x02` FEC
-status, and `0x03` terminal receipt (empty). FEC status contains
+status, `0x03` terminal receipt (empty), `0x04` quality-work prompt, and
+`0x05` Stop-work prompt. The quality prompt is exactly `operation_id` (16
+canonical UUID bytes) followed by `revision` (nonzero u64). The Stop prompt is
+exactly `operation_id` (16 canonical UUID bytes). Prompts never authorize or
+complete work; the gateway acquires the matching durable mTLS work item.
+FEC status contains
 `frame_index` (u32), `highest_received_sequence` (u16),
 `next_contiguous_sequence` (u16), `missing_before_highest` (u16),
 `total_data_packets` (u16), `total_parity_packets` (u16),
@@ -12,7 +12,7 @@
      "3"
    ]
  },
-  "generator_sha256": "00c1905fc611ca9e226cd90da761b48b8e203734b10542befea397a30082d360",
+  "generator_sha256": "c5756780f59a82d8f56762e52f58e22a4d6aca6648157f45e5bad6559b9deeec",
  "protocol_version": "1.0.0",
-  "schema_sha256": "b2353c12269304289b4e872f27cc370ae61b958dea90d9fb7b6ab8afd7d37248"
+  "schema_sha256": "b9e72838b2ae02b3a47e7e2dfa03620b8580f2c98668e6eaf551ea8fb642d297"
 }
@@ -10,6 +10,8 @@ tags:
  - name: resources
  - name: broker
  - name: events
+  - name: session-quality
+  - name: gateway
 paths:
  /api/v1/auth/login:
    post:
@@ -326,6 +328,151 @@ paths:
        '401': {$ref: '#/components/responses/Unauthorized'}
        '404': {$ref: '#/components/responses/NotFound'}
        '409': {$ref: '#/components/responses/Conflict'}
+  /api/v1/session-quality-limits:
+    get:
+      tags: [session-quality]
+      operationId: getSessionQualityLimits
+      security: [{nativeBearer: []}]
+      responses:
+        '200': {description: 'Current global native session quality limits. Maximum JSON body: 16384 bytes.', content: {application/json: {schema: {$ref: ../schemas/control-v1.schema.json#/$defs/SessionQualityLimits}}}}
+        '401': {$ref: '#/components/responses/Unauthorized'}
+  /api/v1/session-quality-limits/assignments/{assignment_id}:
+    get:
+      tags: [session-quality]
+      operationId: getAssignmentSessionQualityLimits
+      security: [{nativeBearer: []}]
+      parameters: [{$ref: '#/components/parameters/AssignmentID'}]
+      responses:
+        '200': {description: 'Current assignment-specific native session quality limits. Maximum JSON body: 16384 bytes.', content: {application/json: {schema: {$ref: ../schemas/control-v1.schema.json#/$defs/SessionQualityLimits}}}}
+        '401': {$ref: '#/components/responses/Unauthorized'}
+        '404': {$ref: '#/components/responses/NotFound'}
+  /api/v1/session-quality-limits/pools/{pool_id}:
+    get:
+      tags: [session-quality]
+      operationId: getPoolSessionQualityLimits
+      security: [{nativeBearer: []}]
+      parameters: [{$ref: '#/components/parameters/PoolID'}]
+      responses:
+        '200': {description: 'Current pool-specific native session quality limits. Maximum JSON body: 16384 bytes.', content: {application/json: {schema: {$ref: ../schemas/control-v1.schema.json#/$defs/SessionQualityLimits}}}}
+        '401': {$ref: '#/components/responses/Unauthorized'}
+        '404': {$ref: '#/components/responses/NotFound'}
+  /api/v1/admin/entitlements/{entitlement_id}/display-limit-override:
+    patch:
+      tags: [session-quality]
+      operationId: updateEntitlementDisplayLimitOverride
+      security:
+        - browserSession: []
+          browserCsrfCookie: []
+          browserCsrfHeader: []
+      parameters: [{$ref: '#/components/parameters/EntitlementID'}]
+      requestBody: {required: true, description: 'Maximum JSON body: 16384 bytes.', content: {application/json: {schema: {$ref: ../schemas/control-v1.schema.json#/$defs/DisplayLimitOverrideRequest}}}}
+      responses:
+        '204': {description: Direct entitlement display override updated.}
+        '400': {$ref: '#/components/responses/InvalidRequest'}
+        '401': {$ref: '#/components/responses/Unauthorized'}
+        '403': {$ref: '#/components/responses/Forbidden'}
+        '404': {$ref: '#/components/responses/NotFound'}
+        '409': {$ref: '#/components/responses/Conflict'}
+  /api/v1/broker/sessions/{session_id}/quality-changes:
+    post:
+      tags: [session-quality]
+      operationId: createSessionQualityChange
+      description: The owning principal and active device/key MUST match the subject-scoped broker session. Maximum JSON body: 16384 bytes.
+      security: [{nativeBearer: []}]
+      parameters: [{$ref: '#/components/parameters/SessionID'}, {$ref: '#/components/parameters/IdempotencyKey'}]
+      requestBody: {required: true, description: 'Maximum JSON body: 16384 bytes.', content: {application/json: {schema: {$ref: ../schemas/control-v1.schema.json#/$defs/QualityChangeRequest}}}}
+      responses:
+        '201': {description: 'Durable quality change created. Maximum JSON body: 16384 bytes.', content: {application/json: {schema: {$ref: ../schemas/control-v1.schema.json#/$defs/QualityChangeOperation}}}}
+        '200': {description: 'Existing idempotent quality change returned. Maximum JSON body: 16384 bytes.', content: {application/json: {schema: {$ref: ../schemas/control-v1.schema.json#/$defs/QualityChangeOperation}}}}
+        '400': {$ref: '#/components/responses/InvalidRequest'}
+        '401': {$ref: '#/components/responses/Unauthorized'}
+        '404': {$ref: '#/components/responses/NotFound'}
+        '409': {$ref: '#/components/responses/Conflict'}
+  /api/v1/broker/sessions/{session_id}/quality-changes/{operation_id}:
+    get:
+      tags: [session-quality]
+      operationId: getSessionQualityChange
+      description: The owning principal and active device/key MUST match the subject-scoped broker session and operation. Maximum JSON body: 16384 bytes.
+      security: [{nativeBearer: []}]
+      parameters: [{$ref: '#/components/parameters/SessionID'}, {$ref: '#/components/parameters/OperationID'}]
+      responses:
+        '200': {description: 'Durable quality change state. Maximum JSON body: 16384 bytes.', content: {application/json: {schema: {$ref: ../schemas/control-v1.schema.json#/$defs/QualityChangeOperation}}}}
+        '401': {$ref: '#/components/responses/Unauthorized'}
+        '404': {$ref: '#/components/responses/NotFound'}
+  /api/v1/broker/sessions/{session_id}/stop-operations:
+    post:
+      tags: [session-quality]
+      operationId: createSessionStopOperation
+      description: The owning principal and active device/key MUST match the subject-scoped broker session. Maximum JSON body: 16384 bytes.
+      security: [{nativeBearer: []}]
+      parameters: [{$ref: '#/components/parameters/SessionID'}, {$ref: '#/components/parameters/IdempotencyKey'}]
+      responses:
+        '201': {description: 'Durable Stop operation created. Maximum JSON body: 16384 bytes.', content: {application/json: {schema: {$ref: ../schemas/control-v1.schema.json#/$defs/StopOperation}}}}
+        '200': {description: 'Existing idempotent Stop operation returned. Maximum JSON body: 16384 bytes.', content: {application/json: {schema: {$ref: ../schemas/control-v1.schema.json#/$defs/StopOperation}}}}
+        '401': {$ref: '#/components/responses/Unauthorized'}
+        '404': {$ref: '#/components/responses/NotFound'}
+        '409': {$ref: '#/components/responses/Conflict'}
+  /api/v1/broker/sessions/{session_id}/stop-operations/{operation_id}:
+    get:
+      tags: [session-quality]
+      operationId: getSessionStopOperation
+      description: The owning principal and active device/key MUST match the subject-scoped broker session and operation. Maximum JSON body: 16384 bytes.
+      security: [{nativeBearer: []}]
+      parameters: [{$ref: '#/components/parameters/SessionID'}, {$ref: '#/components/parameters/OperationID'}]
+      responses:
+        '200': {description: 'Durable Stop operation state. Maximum JSON body: 16384 bytes.', content: {application/json: {schema: {$ref: ../schemas/control-v1.schema.json#/$defs/StopOperation}}}}
+        '401': {$ref: '#/components/responses/Unauthorized'}
+        '404': {$ref: '#/components/responses/NotFound'}
+  /api/v1/gateway/quality-work:
+    post:
+      tags: [gateway]
+      operationId: acquireGatewayQualityWork
+      description: The authenticated gateway mTLS certificate identity MUST match `gateway_id`; Server authority MUST match the session, gateway, reconnect sequence, and supplied operation/revision/lease generation coordinates. A `poll` acquisition omits unknown operation coordinates and discovers pending session work after a lost prompt; `prompt` and `observation` coordinates MUST match exactly. Maximum JSON body: 16384 bytes.
+      security: [{gatewayMutualTLS: []}]
+      requestBody: {required: true, description: 'Maximum JSON body: 16384 bytes.', content: {application/json: {schema: {$ref: ../schemas/control-v1.schema.json#/$defs/GatewayQualityWorkRequest}}}}
+      responses:
+        '200': {description: 'Leased quality work or reconciliation observation. Maximum JSON body: 16384 bytes.', content: {application/json: {schema: {$ref: ../schemas/control-v1.schema.json#/$defs/GatewayQualityWork}}}}
+        '204': {description: No matching work is available.}
+        '400': {$ref: '#/components/responses/InvalidRequest'}
+        '401': {$ref: '#/components/responses/Unauthorized'}
+        '409': {$ref: '#/components/responses/Conflict'}
+  /api/v1/gateway/quality-ack:
+    post:
+      tags: [gateway]
+      operationId: acknowledgeGatewayQualityWork
+      description: The authenticated gateway mTLS certificate identity MUST match `gateway_id`; Server authority MUST exactly match the session, gateway, reconnect sequence, operation, revision, and monotonic lease generation tuple. Stale lease generations MUST be rejected. `applied` requires `current_applied_revision == revision`; `proven_prior` requires `current_applied_revision < revision`; `unknown` forbids `current_applied_revision` and makes no applied-revision assertion. Maximum JSON body: 16384 bytes.
+      security: [{gatewayMutualTLS: []}]
+      requestBody: {required: true, description: 'Maximum JSON body: 16384 bytes.', content: {application/json: {schema: {$ref: ../schemas/control-v1.schema.json#/$defs/GatewayQualityAck}}}}
+      responses:
+        '204': {description: Quality acknowledgement committed idempotently.}
+        '400': {$ref: '#/components/responses/InvalidRequest'}
+        '401': {$ref: '#/components/responses/Unauthorized'}
+        '409': {$ref: '#/components/responses/Conflict'}
+  /api/v1/gateway/stop-work:
+    post:
+      tags: [gateway]
+      operationId: acquireGatewayStopWork
+      description: The authenticated gateway mTLS certificate identity MUST match `gateway_id`; Server authority MUST match the session, gateway, reconnect sequence, and any supplied operation coordinate. A `poll` acquisition omits the unknown operation ID and discovers pending session work after a lost prompt; a `prompt` coordinate MUST match exactly. Maximum JSON body: 16384 bytes.
+      security: [{gatewayMutualTLS: []}]
+      requestBody: {required: true, description: 'Maximum JSON body: 16384 bytes.', content: {application/json: {schema: {$ref: ../schemas/control-v1.schema.json#/$defs/GatewayStopWorkRequest}}}}
+      responses:
+        '200': {description: 'One-way non-reissued Stop work claim. Maximum JSON body: 16384 bytes.', content: {application/json: {schema: {$ref: ../schemas/control-v1.schema.json#/$defs/GatewayStopWork}}}}
+        '204': {description: No matching Stop work is available.}
+        '400': {$ref: '#/components/responses/InvalidRequest'}
+        '401': {$ref: '#/components/responses/Unauthorized'}
+        '409': {$ref: '#/components/responses/Conflict'}
+  /api/v1/gateway/stop-ack:
+    post:
+      tags: [gateway]
+      operationId: acknowledgeGatewayStopWork
+      description: The authenticated gateway mTLS certificate identity MUST match `gateway_id`; Server authority MUST exactly match the session, gateway, reconnect sequence, and operation tuple. Maximum JSON body: 16384 bytes.
+      security: [{gatewayMutualTLS: []}]
+      requestBody: {required: true, description: 'Maximum JSON body: 16384 bytes.', content: {application/json: {schema: {$ref: ../schemas/control-v1.schema.json#/$defs/GatewayStopAck}}}}
+      responses:
+        '204': {description: Stop acknowledgement committed idempotently.}
+        '400': {$ref: '#/components/responses/InvalidRequest'}
+        '401': {$ref: '#/components/responses/Unauthorized'}
+        '409': {$ref: '#/components/responses/Conflict'}
  /api/v1/events:
    get:
      tags: [events]
@@ -385,6 +532,8 @@ components:
      type: http
      scheme: bearer
      bearerFormat: opaque
+    gatewayMutualTLS:
+      type: mutualTLS
  parameters:
    DeviceID:
      name: device_id
@@ -396,6 +545,26 @@ components:
      in: path
      required: true
      schema: {type: string, minLength: 1, maxLength: 128}
+    AssignmentID:
+      name: assignment_id
+      in: path
+      required: true
+      schema: {type: string, minLength: 1, maxLength: 128}
+    PoolID:
+      name: pool_id
+      in: path
+      required: true
+      schema: {type: string, minLength: 1, maxLength: 128}
+    EntitlementID:
+      name: entitlement_id
+      in: path
+      required: true
+      schema: {type: string, minLength: 1, maxLength: 128}
+    OperationID:
+      name: operation_id
+      in: path
+      required: true
+      schema: {type: string, format: uuid, pattern: '^(?!00000000-0000-0000-0000-000000000000$)[0-9a-f]{8}-[0-9a-f]{4}-[0-9a-f]{4}-[0-9a-f]{4}-[0-9a-f]{12}$'}
    Limit:
      name: limit
      in: query
@@ -54,9 +54,56 @@ message CapabilityProfile {
  string transport = 1;
  string framing = 2;
  string media = 3;
-  string audio = 4;
+  reserved 4;
  string source_rate_control = 5;
-  repeated string client_decode = 6;
+  reserved 6;
+  repeated VideoProfile video_profiles = 7;
+  repeated AudioProfile audio_profiles = 8;
+}
+
+message VideoProfile {
+  string codec = 1;
+  uint32 bit_depth = 2;
+  string chroma_subsampling = 3;
+  string color_space = 4;
+  string transfer_function = 5;
+}
+
+message AudioProfile {
+  string codec = 1;
+  uint32 sample_rate_hz = 2;
+  uint32 channels = 3;
+  string channel_layout = 4;
+  uint32 packet_duration_ms = 5;
+}
+
+message DisplayMode {
+  uint32 resolution_width = 1;
+  uint32 resolution_height = 2;
+  uint32 fps = 3;
+}
+
+message SessionAdjustment {
+  string display_reason = 1;
+  string bitrate_reason = 2;
+}
+
+message SelectedSessionDescriptor {
+  VideoProfile video_profile = 1;
+  AudioProfile audio_profile = 2;
+  DisplayMode display_mode = 3;
+  uint64 bitrate_target_kbps = 4;
+  uint64 bitrate_maximum_kbps = 5;
+  SessionAdjustment adjustment = 6;
+  string media_timestamp_basis = 7;
+}
+
+message ProviderStreamPolicy {
+  VideoProfile video_profile = 1;
+  AudioProfile audio_profile = 2;
+  DisplayMode display_mode = 3;
+  uint64 bitrate_target_kbps = 4;
+  uint64 bitrate_maximum_kbps = 5;
 }

 message GatewayRegistration {
@@ -115,6 +162,7 @@ message SessionAuthority {
  CapabilityProfile capabilities = 7;
  string provider_profile = 8;
  string provider_identity = 9;
+  SelectedSessionDescriptor selected_descriptor = 10;
 }

 message ClientSessionAuthority {
@@ -125,6 +173,7 @@ message ClientSessionAuthority {
  uint64 reconnect_sequence = 5;
  google.protobuf.Timestamp expires_at = 6;
  CapabilityProfile capabilities = 7;
+  SelectedSessionDescriptor selected_descriptor = 8;
 }

 message ProviderSessionWork {
@@ -147,6 +196,73 @@ message ProviderSessionWork {
  string client_id = 17;
  ClipboardPolicy clipboard_policy = 18;
  bool provider_application_termination_allowed = 19;
+  ProviderStreamPolicy stream_policy = 20;
+}
+
+message GatewayQualityWorkRequest {
+  string version = 1;
+  string session_id = 2;
+  string gateway_id = 3;
+  uint64 reconnect_sequence = 4;
+  string operation_id = 5;
+  optional uint64 revision = 6;
+  optional uint64 current_applied_revision = 7;
+  string acquisition = 8;
+  optional uint64 lease_generation = 9;
+}
+
+message GatewayQualityWork {
+  string version = 1;
+  string session_id = 2;
+  string gateway_id = 3;
+  uint64 reconnect_sequence = 4;
+  string operation_id = 5;
+  uint64 revision = 6;
+  google.protobuf.Timestamp lease_expires_at = 7;
+  SelectedSessionDescriptor selected_descriptor = 8;
+  optional uint64 current_applied_revision = 9;
+  uint64 lease_generation = 10;
+}
+
+message GatewayQualityAck {
+  string version = 1;
+  string session_id = 2;
+  string gateway_id = 3;
+  uint64 reconnect_sequence = 4;
+  string operation_id = 5;
+  uint64 revision = 6;
+  string outcome = 7;
+  optional uint64 current_applied_revision = 8;
+  string failure_code = 9;
+  uint64 lease_generation = 10;
+}
+
+message GatewayStopWork {
+  string version = 1;
+  string session_id = 2;
+  string gateway_id = 3;
+  uint64 reconnect_sequence = 4;
+  string operation_id = 5;
+  uint32 attempt = 6;
+}
+
+message GatewayStopWorkRequest {
+  string version = 1;
+  string session_id = 2;
+  string gateway_id = 3;
+  uint64 reconnect_sequence = 4;
+  string operation_id = 5;
+  string acquisition = 6;
+}
+
+message GatewayStopAck {
+  string version = 1;
+  string session_id = 2;
+  string gateway_id = 3;
+  uint64 reconnect_sequence = 4;
+  string operation_id = 5;
+  string outcome = 6;
+  string failure_code = 7;
 }

 message ClipboardPolicy {
@@ -8,6 +8,9 @@
  "datagrams": [
    {"id": "control.ack.v1", "direction": "bidirectional", "max_payload_bytes": 1024, "payload_profile": "gateway-feedback-v1"},
    {"id": "control.cancel.v1", "direction": "client-to-server", "max_payload_bytes": 2048},
+    {"id": "session.quality.prompt.v1", "direction": "client-to-server", "max_payload_bytes": 32, "payload_profile": "gateway-feedback-v1"},
+    {"id": "session.stop.prompt.v1", "direction": "client-to-server", "max_payload_bytes": 24, "payload_profile": "gateway-feedback-v1"},
+    {"id": "controller.arrival.v1", "direction": "client-to-server", "max_payload_bytes": 14, "payload_profile": "gateway-input-v1"},
    {"id": "clipboard.text.v1", "direction": "bidirectional", "max_payload_bytes": 65536},
    {"id": "media.video.v1", "direction": "server-to-client", "max_payload_bytes": 1200},
    {"id": "media.audio.v1", "direction": "server-to-client", "max_payload_bytes": 1200},
@@ -7,6 +7,10 @@
    {"id": "clipboard.text.v1", "direction": "bidirectional", "max_frame_bytes": 65536},
    {"id": "display.request.v1", "direction": "client-to-server", "max_frame_bytes": 65536},
    {"id": "input.absolute.v1", "direction": "client-to-server", "max_frame_bytes": 14},
-    {"id": "input.scroll.v1", "direction": "client-to-server", "max_frame_bytes": 10}
+    {"id": "input.scroll.v1", "direction": "client-to-server", "max_frame_bytes": 10},
+    {"id": "video.profile.v1", "direction": "bidirectional", "max_frame_bytes": 65536},
+    {"id": "session.quality.v1", "direction": "bidirectional", "max_frame_bytes": 32},
+    {"id": "session.stop.v1", "direction": "bidirectional", "max_frame_bytes": 24},
+    {"id": "controller.arrival.v1", "direction": "client-to-server", "max_frame_bytes": 14}
  ]
 }
@@ -64,22 +64,24 @@
    "AssignedDesktop": {
      "type": "object",
      "additionalProperties": false,
-      "required": ["assignment_id", "pool_id", "name", "availability"],
+      "required": ["assignment_id", "pool_id", "name", "availability", "quality_limits"],
      "properties": {
        "assignment_id": {"type": "string", "minLength": 1, "maxLength": 128},
        "pool_id": {"type": "string", "minLength": 1, "maxLength": 128},
        "name": {"type": "string", "minLength": 1, "maxLength": 256},
-        "availability": {"type": "string", "minLength": 1, "maxLength": 64}
+        "availability": {"type": "string", "minLength": 1, "maxLength": 64},
+        "quality_limits": {"$ref": "#/$defs/SessionQualityLimits"}
      }
    },
    "EntitledPool": {
      "type": "object",
      "additionalProperties": false,
-      "required": ["pool_id", "name", "assignment_state"],
+      "required": ["pool_id", "name", "assignment_state", "quality_limits"],
      "properties": {
        "pool_id": {"type": "string", "minLength": 1, "maxLength": 128},
        "name": {"type": "string", "minLength": 1, "maxLength": 256},
-        "assignment_state": {"type": "string", "minLength": 1, "maxLength": 64}
+        "assignment_state": {"type": "string", "minLength": 1, "maxLength": 64},
+        "quality_limits": {"$ref": "#/$defs/SessionQualityLimits"}
      }
    },
    "ResourceList": {
@@ -232,32 +234,106 @@
        "fps": {"type": "integer", "minimum": 1, "maximum": 240}
      }
    },
+    "VideoProfile": {
+      "type": "object",
+      "additionalProperties": false,
+      "required": ["codec", "bit_depth", "chroma_subsampling", "color_space", "transfer_function"],
+      "properties": {
+        "codec": {"type": "string", "enum": ["h264", "hevc", "av1"]},
+        "bit_depth": {"type": "integer", "minimum": 8, "maximum": 8},
+        "chroma_subsampling": {"type": "string", "const": "4:2:0"},
+        "color_space": {"type": "string", "const": "bt709-limited"},
+        "transfer_function": {"type": "string", "const": "sdr"}
+      }
+    },
+    "AudioProfile": {
+      "type": "object",
+      "additionalProperties": false,
+      "required": ["codec", "sample_rate_hz", "channels", "channel_layout", "packet_duration_ms"],
+      "properties": {
+        "codec": {"type": "string", "const": "opus"},
+        "sample_rate_hz": {"type": "integer", "minimum": 48000, "maximum": 48000},
+        "channels": {"type": "integer", "minimum": 2, "maximum": 2},
+        "channel_layout": {"type": "string", "const": "stereo"},
+        "packet_duration_ms": {"type": "integer", "minimum": 5, "maximum": 5}
+      }
+    },
+    "BitratePreference": {
+      "type": "object",
+      "additionalProperties": false,
+      "required": ["mode"],
+      "properties": {
+        "mode": {"type": "string", "enum": ["auto", "explicit"]},
+        "target_kbps": {"type": "integer", "minimum": 100, "maximum": 1000000, "x-optional-pointer": true}
+      }
+    },
+    "SessionQualityLimits": {
+      "type": "object",
+      "x-max-bytes": 16384,
+      "additionalProperties": false,
+      "required": ["policy_version_id", "policy_display_limit", "selectable_display_maximum", "display_limit_override", "bitrate_minimum_kbps", "bitrate_target_kbps", "bitrate_maximum_kbps"],
+      "properties": {
+        "policy_version_id": {"type": "string", "minLength": 1, "maxLength": 128},
+        "policy_display_limit": {"$ref": "#/$defs/DisplayMode"},
+        "selectable_display_maximum": {"$ref": "#/$defs/DisplayMode"},
+        "display_limit_override": {"type": "boolean"},
+        "bitrate_minimum_kbps": {"type": "integer", "minimum": 100, "maximum": 1000000},
+        "bitrate_target_kbps": {"type": "integer", "minimum": 100, "maximum": 1000000},
+        "bitrate_maximum_kbps": {"type": "integer", "minimum": 100, "maximum": 1000000}
+      }
+    },
+    "SessionAdjustment": {
+      "type": "object",
+      "additionalProperties": false,
+      "required": ["display_reason", "bitrate_reason"],
+      "properties": {
+        "display_reason": {"type": "string", "enum": ["none", "policy_clamp", "direct_entitlement_override"]},
+        "bitrate_reason": {"type": "string", "enum": ["none", "policy_default", "session_ceiling_clamp", "aggregate_capacity_clamp"]}
+      }
+    },
+    "SelectedSessionDescriptor": {
+      "type": "object",
+      "additionalProperties": false,
+      "required": ["video_profile", "audio_profile", "display_mode", "bitrate_target_kbps", "bitrate_maximum_kbps", "adjustment", "media_timestamp_basis"],
+      "properties": {
+        "video_profile": {"$ref": "#/$defs/VideoProfile"},
+        "audio_profile": {"$ref": "#/$defs/AudioProfile"},
+        "display_mode": {"$ref": "#/$defs/DisplayMode"},
+        "bitrate_target_kbps": {"type": "integer", "minimum": 100, "maximum": 1000000},
+        "bitrate_maximum_kbps": {"type": "integer", "minimum": 100, "maximum": 1000000},
+        "adjustment": {"$ref": "#/$defs/SessionAdjustment"},
+        "media_timestamp_basis": {"type": "string", "const": "gateway-send-wall-clock-ms"}
+      }
+    },
    "SessionRequest": {
      "type": "object",
      "additionalProperties": false,
-      "required": ["client_device_id", "device_key_id", "pool_id", "idempotency_key"],
+      "required": ["client_device_id", "device_key_id", "pool_id", "idempotency_key", "video_profiles", "bitrate_preference"],
      "properties": {
        "client_device_id": {"type": "string", "minLength": 1, "maxLength": 128},
        "device_key_id": {"type": "string", "minLength": 1, "maxLength": 128},
        "pool_id": {"type": "string", "minLength": 1, "maxLength": 128},
        "idempotency_key": {"type": "string", "minLength": 1, "maxLength": 256},
+        "video_profiles": {"type": "array", "minItems": 1, "maxItems": 12, "uniqueItems": true, "items": {"$ref": "#/$defs/VideoProfile"}},
+        "bitrate_preference": {"$ref": "#/$defs/BitratePreference"},
        "requested_display_mode": {"$ref": "#/$defs/DisplayMode"}
      }
    },
    "ReconnectRequest": {
      "type": "object",
      "additionalProperties": false,
-      "required": ["client_device_id", "device_key_id", "expected_version"],
+      "required": ["client_device_id", "device_key_id", "expected_version", "display_relaunch_confirmed"],
      "properties": {
        "client_device_id": {"type": "string", "minLength": 1, "maxLength": 128},
        "device_key_id": {"type": "string", "minLength": 1, "maxLength": 128},
-        "expected_version": {"type": "integer", "minimum": 1}
+        "expected_version": {"type": "integer", "minimum": 1},
+        "display_relaunch_confirmed": {"type": "boolean"}
      }
    },
    "BrokerSession": {
      "type": "object",
      "additionalProperties": false,
-      "required": ["id", "principal_id", "pool_id", "state", "policy_snapshot", "cleanup_state", "idempotency_key", "correlation_id", "requested_at", "version"],
+      "required": ["id", "principal_id", "pool_id", "state", "policy_snapshot", "cleanup_state", "idempotency_key", "correlation_id", "requested_at", "version", "requested_video_profiles", "requested_bitrate_preference"],
      "properties": {
        "id": {"type": "string", "minLength": 1, "maxLength": 128},
        "principal_id": {"type": "string", "minLength": 1, "maxLength": 128},
@@ -275,7 +351,10 @@
        "ended_at": {"type": "string", "format": "date-time", "maxLength": 64},
        "version": {"type": "integer", "minimum": 1},
        "requested_display_mode": {"$ref": "#/$defs/DisplayMode"},
-        "effective_display_mode": {"$ref": "#/$defs/DisplayMode"}
+        "effective_display_mode": {"$ref": "#/$defs/DisplayMode"},
+        "requested_video_profiles": {"type": "array", "minItems": 1, "maxItems": 12, "uniqueItems": true, "items": {"$ref": "#/$defs/VideoProfile"}},
+        "requested_bitrate_preference": {"$ref": "#/$defs/BitratePreference"},
+        "selected_descriptor": {"$ref": "#/$defs/SelectedSessionDescriptor"}
      }
    },
    "AllocationPolicy": {
@@ -297,7 +376,7 @@
    "ConnectionManifest": {
      "type": "object",
      "additionalProperties": false,
-      "required": ["version", "purpose", "session_id", "reconnect_sequence", "gateway", "tunnel", "profile", "grant", "correlation_id"],
+      "required": ["version", "purpose", "session_id", "reconnect_sequence", "gateway", "tunnel", "profile", "grant", "correlation_id", "selected_descriptor"],
      "properties": {
        "version": {"type": "string", "const": "1"},
        "purpose": {"type": "string", "enum": ["launch", "reconnect"]},
@@ -307,7 +386,8 @@
        "tunnel": {"$ref": "#/$defs/ManifestTunnel"},
        "profile": {"$ref": "#/$defs/ManifestProfile"},
        "grant": {"$ref": "#/$defs/GrantReference"},
-        "correlation_id": {"type": "string", "minLength": 1, "maxLength": 128}
+        "correlation_id": {"type": "string", "minLength": 1, "maxLength": 128},
+        "selected_descriptor": {"$ref": "#/$defs/SelectedSessionDescriptor"}
      }
    },
    "ManifestGateway": {
@@ -431,20 +511,14 @@
    "CapabilityProfile": {
      "type": "object",
      "additionalProperties": false,
-      "required": ["transport", "framing", "media", "audio", "source_rate_control", "client_decode"],
+      "required": ["transport", "framing", "media", "source_rate_control", "video_profiles", "audio_profiles"],
      "properties": {
        "transport": {"type": "string", "minLength": 1, "maxLength": 64},
        "framing": {"type": "string", "enum": ["datagram-v1", "datagram-v2"]},
        "media": {"type": "string", "minLength": 1, "maxLength": 64},
-        "audio": {"type": "string", "minLength": 1, "maxLength": 64},
        "source_rate_control": {"type": "string", "minLength": 1, "maxLength": 64},
-        "client_decode": {
-          "type": "array",
-          "minItems": 1,
-          "maxItems": 2,
-          "uniqueItems": true,
-          "items": {"type": "string", "enum": ["h264-opus", "hevc-opus"]}
-        }
+        "video_profiles": {"type": "array", "minItems": 1, "maxItems": 12, "uniqueItems": true, "items": {"$ref": "#/$defs/VideoProfile"}},
+        "audio_profiles": {"type": "array", "minItems": 1, "maxItems": 1, "uniqueItems": true, "items": {"$ref": "#/$defs/AudioProfile"}}
      }
    },
    "GatewayRegistration": {
@@ -538,7 +612,7 @@
    "SessionAuthority": {
      "type": "object",
      "additionalProperties": false,
-      "required": ["version", "session_id", "gateway_id", "audience", "reconnect_sequence", "expires_at", "capabilities", "provider_profile", "provider_identity"],
+      "required": ["version", "session_id", "gateway_id", "audience", "reconnect_sequence", "expires_at", "capabilities", "provider_profile", "provider_identity", "selected_descriptor"],
      "properties": {
        "version": {"type": "string", "const": "1"},
        "session_id": {"type": "string", "minLength": 1, "maxLength": 128},
@@ -548,13 +622,14 @@
        "expires_at": {"type": "string", "format": "date-time", "maxLength": 64},
        "capabilities": {"$ref": "#/$defs/CapabilityProfile"},
        "provider_profile": {"type": "string", "enum": ["apollo"]},
-        "provider_identity": {"type": "string", "minLength": 1, "maxLength": 256}
+        "provider_identity": {"type": "string", "minLength": 1, "maxLength": 256},
+        "selected_descriptor": {"$ref": "#/$defs/SelectedSessionDescriptor"}
      }
    },
    "ClientSessionAuthority": {
      "type": "object",
      "additionalProperties": false,
-      "required": ["version", "session_id", "gateway_id", "audience", "reconnect_sequence", "expires_at", "capabilities"],
+      "required": ["version", "session_id", "gateway_id", "audience", "reconnect_sequence", "expires_at", "capabilities", "selected_descriptor"],
      "properties": {
        "version": {"type": "string", "const": "1"},
        "session_id": {"type": "string", "minLength": 1, "maxLength": 128},
@@ -562,20 +637,155 @@
        "audience": {"type": "string", "minLength": 1, "maxLength": 256},
        "reconnect_sequence": {"type": "integer", "minimum": 0},
        "expires_at": {"type": "string", "format": "date-time", "pattern": "^[0-9]{4}-[0-9]{2}-[0-9]{2}T[0-9]{2}:[0-9]{2}:[0-9]{2}Z$", "maxLength": 64},
-        "capabilities": {"$ref": "#/$defs/CapabilityProfile"}
+        "capabilities": {"$ref": "#/$defs/CapabilityProfile"},
+        "selected_descriptor": {"$ref": "#/$defs/SelectedSessionDescriptor"}
      }
    },
    "ProviderStreamPolicy": {
      "type": "object",
      "additionalProperties": false,
-      "required": ["resolution_width", "resolution_height", "fps", "codec", "bitrate_kbps", "audio_enabled"],
+      "required": ["video_profile", "audio_profile", "display_mode", "bitrate_target_kbps", "bitrate_maximum_kbps"],
      "properties": {
-        "resolution_width": {"type": "integer", "minimum": 320, "maximum": 16384},
-        "resolution_height": {"type": "integer", "minimum": 200, "maximum": 8640},
-        "fps": {"type": "integer", "minimum": 1, "maximum": 240},
-        "codec": {"type": "string", "enum": ["H264", "HEVC", "AV1"]},
-        "bitrate_kbps": {"type": "integer", "minimum": 100, "maximum": 1000000},
-        "audio_enabled": {"type": "boolean"}
+        "video_profile": {"$ref": "#/$defs/VideoProfile"},
+        "audio_profile": {"$ref": "#/$defs/AudioProfile"},
+        "display_mode": {"$ref": "#/$defs/DisplayMode"},
+        "bitrate_target_kbps": {"type": "integer", "minimum": 100, "maximum": 1000000},
+        "bitrate_maximum_kbps": {"type": "integer", "minimum": 100, "maximum": 1000000}
+      }
+    },
+    "DisplayLimitOverrideRequest": {
+      "type": "object",
+      "x-max-bytes": 16384,
+      "additionalProperties": false,
+      "required": ["allow_display_limit_override", "expected_version"],
+      "properties": {
+        "allow_display_limit_override": {"type": "boolean"},
+        "expected_version": {"type": "integer", "minimum": 1}
+      }
+    },
+    "QualityChangeRequest": {
+      "type": "object",
+      "x-max-bytes": 16384,
+      "additionalProperties": false,
+      "required": ["bitrate_preference", "expected_session_version", "expected_policy_version"],
+      "properties": {
+        "bitrate_preference": {"$ref": "#/$defs/BitratePreference"},
+        "expected_session_version": {"type": "integer", "minimum": 1},
+        "expected_policy_version": {"type": "string", "minLength": 1, "maxLength": 128}
+      }
+    },
+    "QualityChangeOperation": {
+      "type": "object",
+      "x-max-bytes": 16384,
+      "additionalProperties": false,
+      "required": ["operation_id", "session_id", "revision", "state", "requested_bitrate_preference", "effective_bitrate_kbps", "governing_policy_version", "session_version", "created_at", "deadline_at", "updated_at"],
+      "properties": {
+        "operation_id": {"type": "string", "format": "uuid", "pattern": "^(?!00000000-0000-0000-0000-000000000000$)[0-9a-f]{8}-[0-9a-f]{4}-[0-9a-f]{4}-[0-9a-f]{4}-[0-9a-f]{12}$", "minLength": 36, "maxLength": 36},
+        "session_id": {"type": "string", "minLength": 1, "maxLength": 128},
+        "revision": {"type": "integer", "minimum": 1},
+        "state": {"type": "string", "enum": ["pending", "applying", "applied", "failed", "timed_out"]},
+        "requested_bitrate_preference": {"$ref": "#/$defs/BitratePreference"},
+        "effective_bitrate_kbps": {"type": "integer", "minimum": 100, "maximum": 1000000},
+        "governing_policy_version": {"type": "string", "minLength": 1, "maxLength": 128},
+        "session_version": {"type": "integer", "minimum": 1},
+        "created_at": {"type": "string", "format": "date-time", "pattern": "^[0-9]{4}-[0-9]{2}-[0-9]{2}T[0-9]{2}:[0-9]{2}:[0-9]{2}(?:\\.[0-9]{0,8}[1-9])?Z$", "maxLength": 64},
+        "deadline_at": {"type": "string", "format": "date-time", "pattern": "^[0-9]{4}-[0-9]{2}-[0-9]{2}T[0-9]{2}:[0-9]{2}:[0-9]{2}(?:\\.[0-9]{0,8}[1-9])?Z$", "maxLength": 64},
+        "updated_at": {"type": "string", "format": "date-time", "pattern": "^[0-9]{4}-[0-9]{2}-[0-9]{2}T[0-9]{2}:[0-9]{2}:[0-9]{2}(?:\\.[0-9]{0,8}[1-9])?Z$", "maxLength": 64},
+        "failure_code": {"type": "string", "minLength": 1, "maxLength": 128}
+      }
+    },
+    "StopOperation": {
+      "type": "object",
+      "x-max-bytes": 16384,
+      "additionalProperties": false,
+      "required": ["operation_id", "session_id", "state", "session_version", "created_at", "deadline_at", "updated_at"],
+      "properties": {
+        "operation_id": {"type": "string", "format": "uuid", "pattern": "^(?!00000000-0000-0000-0000-000000000000$)[0-9a-f]{8}-[0-9a-f]{4}-[0-9a-f]{4}-[0-9a-f]{4}-[0-9a-f]{12}$", "minLength": 36, "maxLength": 36},
+        "session_id": {"type": "string", "minLength": 1, "maxLength": 128},
+        "state": {"type": "string", "enum": ["pending", "attempting", "applied", "failed", "termination_unconfirmed"]},
+        "session_version": {"type": "integer", "minimum": 1},
+        "created_at": {"type": "string", "format": "date-time", "pattern": "^[0-9]{4}-[0-9]{2}-[0-9]{2}T[0-9]{2}:[0-9]{2}:[0-9]{2}(?:\\.[0-9]{0,8}[1-9])?Z$", "maxLength": 64},
+        "deadline_at": {"type": "string", "format": "date-time", "pattern": "^[0-9]{4}-[0-9]{2}-[0-9]{2}T[0-9]{2}:[0-9]{2}:[0-9]{2}(?:\\.[0-9]{0,8}[1-9])?Z$", "maxLength": 64},
+        "updated_at": {"type": "string", "format": "date-time", "pattern": "^[0-9]{4}-[0-9]{2}-[0-9]{2}T[0-9]{2}:[0-9]{2}:[0-9]{2}(?:\\.[0-9]{0,8}[1-9])?Z$", "maxLength": 64},
+        "failure_code": {"type": "string", "minLength": 1, "maxLength": 128}
+      }
+    },
+    "GatewayQualityWorkRequest": {
+      "type": "object", "additionalProperties": false,
+      "x-max-bytes": 16384,
+      "required": ["version", "session_id", "gateway_id", "reconnect_sequence", "acquisition"],
+      "properties": {
+        "version": {"type": "string", "const": "1"}, "session_id": {"type": "string", "minLength": 1, "maxLength": 128},
+        "gateway_id": {"type": "string", "minLength": 1, "maxLength": 128}, "reconnect_sequence": {"type": "integer", "minimum": 0},
+        "acquisition": {"type": "string", "enum": ["poll", "prompt", "observation"]},
+        "operation_id": {"type": "string", "format": "uuid", "pattern": "^(?!00000000-0000-0000-0000-000000000000$)[0-9a-f]{8}-[0-9a-f]{4}-[0-9a-f]{4}-[0-9a-f]{4}-[0-9a-f]{12}$", "minLength": 36, "maxLength": 36},
+        "revision": {"type": "integer", "minimum": 1, "x-optional-pointer": true},
+        "lease_generation": {"type": "integer", "minimum": 1, "x-optional-pointer": true},
+        "current_applied_revision": {"type": "integer", "minimum": 0, "x-optional-pointer": true}
+      }
+    },
+    "GatewayQualityWork": {
+      "type": "object", "additionalProperties": false,
+      "x-max-bytes": 16384,
+      "required": ["version", "session_id", "gateway_id", "reconnect_sequence", "operation_id", "revision", "lease_generation", "lease_expires_at", "selected_descriptor"],
+      "properties": {
+        "version": {"type": "string", "const": "1"}, "session_id": {"type": "string", "minLength": 1, "maxLength": 128},
+        "gateway_id": {"type": "string", "minLength": 1, "maxLength": 128}, "reconnect_sequence": {"type": "integer", "minimum": 0},
+        "operation_id": {"type": "string", "format": "uuid", "pattern": "^(?!00000000-0000-0000-0000-000000000000$)[0-9a-f]{8}-[0-9a-f]{4}-[0-9a-f]{4}-[0-9a-f]{4}-[0-9a-f]{12}$", "minLength": 36, "maxLength": 36}, "revision": {"type": "integer", "minimum": 1},
+        "lease_generation": {"type": "integer", "minimum": 1},
+        "lease_expires_at": {"type": "string", "format": "date-time", "pattern": "^[0-9]{4}-[0-9]{2}-[0-9]{2}T[0-9]{2}:[0-9]{2}:[0-9]{2}(?:\\.[0-9]{0,8}[1-9])?Z$", "maxLength": 64}, "selected_descriptor": {"$ref": "#/$defs/SelectedSessionDescriptor"},
+        "current_applied_revision": {"type": "integer", "minimum": 0, "x-optional-pointer": true}
+      }
+    },
+    "GatewayQualityAck": {
+      "type": "object", "additionalProperties": false,
+      "x-max-bytes": 16384,
+      "description": "Outcome invariants: applied requires current_applied_revision equal to revision; proven_prior requires current_applied_revision strictly less than revision; unknown forbids current_applied_revision and makes no applied-revision assertion.",
+      "required": ["version", "session_id", "gateway_id", "reconnect_sequence", "operation_id", "revision", "lease_generation", "outcome"],
+      "oneOf": [
+        {"properties": {"outcome": {"const": "applied"}}, "required": ["current_applied_revision"]},
+        {"properties": {"outcome": {"const": "proven_prior"}}, "required": ["current_applied_revision"]},
+        {"properties": {"outcome": {"const": "unknown"}}, "not": {"required": ["current_applied_revision"]}}
+      ],
+      "properties": {
+        "version": {"type": "string", "const": "1"}, "session_id": {"type": "string", "minLength": 1, "maxLength": 128},
+        "gateway_id": {"type": "string", "minLength": 1, "maxLength": 128}, "reconnect_sequence": {"type": "integer", "minimum": 0},
+        "operation_id": {"type": "string", "format": "uuid", "pattern": "^(?!00000000-0000-0000-0000-000000000000$)[0-9a-f]{8}-[0-9a-f]{4}-[0-9a-f]{4}-[0-9a-f]{4}-[0-9a-f]{12}$", "minLength": 36, "maxLength": 36}, "revision": {"type": "integer", "minimum": 1},
+        "lease_generation": {"type": "integer", "minimum": 1},
+        "outcome": {"type": "string", "enum": ["applied", "proven_prior", "unknown"]}, "current_applied_revision": {"type": "integer", "minimum": 0, "x-optional-pointer": true},
+        "failure_code": {"type": "string", "minLength": 1, "maxLength": 128}
+      }
+    },
+    "GatewayStopWorkRequest": {
+      "type": "object", "additionalProperties": false,
+      "x-max-bytes": 16384,
+      "required": ["version", "session_id", "gateway_id", "reconnect_sequence", "acquisition"],
+      "properties": {
+        "version": {"type": "string", "const": "1"}, "session_id": {"type": "string", "minLength": 1, "maxLength": 128},
+        "gateway_id": {"type": "string", "minLength": 1, "maxLength": 128}, "reconnect_sequence": {"type": "integer", "minimum": 0},
+        "acquisition": {"type": "string", "enum": ["poll", "prompt"]},
+        "operation_id": {"type": "string", "format": "uuid", "pattern": "^(?!00000000-0000-0000-0000-000000000000$)[0-9a-f]{8}-[0-9a-f]{4}-[0-9a-f]{4}-[0-9a-f]{4}-[0-9a-f]{12}$", "minLength": 36, "maxLength": 36}
+      }
+    },
+    "GatewayStopWork": {
+      "type": "object", "additionalProperties": false,
+      "x-max-bytes": 16384,
+      "required": ["version", "session_id", "gateway_id", "reconnect_sequence", "operation_id", "attempt"],
+      "properties": {
+        "version": {"type": "string", "const": "1"}, "session_id": {"type": "string", "minLength": 1, "maxLength": 128},
+        "gateway_id": {"type": "string", "minLength": 1, "maxLength": 128}, "reconnect_sequence": {"type": "integer", "minimum": 0},
+        "operation_id": {"type": "string", "format": "uuid", "pattern": "^(?!00000000-0000-0000-0000-000000000000$)[0-9a-f]{8}-[0-9a-f]{4}-[0-9a-f]{4}-[0-9a-f]{4}-[0-9a-f]{12}$", "minLength": 36, "maxLength": 36}, "attempt": {"type": "integer", "minimum": 1, "maximum": 1}
+      }
+    },
+    "GatewayStopAck": {
+      "type": "object", "additionalProperties": false,
+      "x-max-bytes": 16384,
+      "required": ["version", "session_id", "gateway_id", "reconnect_sequence", "operation_id", "outcome"],
+      "properties": {
+        "version": {"type": "string", "const": "1"}, "session_id": {"type": "string", "minLength": 1, "maxLength": 128},
+        "gateway_id": {"type": "string", "minLength": 1, "maxLength": 128}, "reconnect_sequence": {"type": "integer", "minimum": 0},
+        "operation_id": {"type": "string", "format": "uuid", "pattern": "^(?!00000000-0000-0000-0000-000000000000$)[0-9a-f]{8}-[0-9a-f]{4}-[0-9a-f]{4}-[0-9a-f]{4}-[0-9a-f]{12}$", "minLength": 36, "maxLength": 36}, "outcome": {"type": "string", "enum": ["applied", "failed", "termination_unconfirmed"]},
+        "failure_code": {"type": "string", "minLength": 1, "maxLength": 128}
      }
    },
    "ProviderSessionWork": {
@@ -11,6 +11,24 @@ import (
 	protocol "git.sechmachine.io.vn/sechmachine/VerseVDI-Protocol/gen/go/protocol"
 )

+func rc6Video(codec string) protocol.VideoProfile {
+	return protocol.VideoProfile{Codec: codec, BitDepth: 8, ChromaSubsampling: "4:2:0", ColorSpace: "bt709-limited", TransferFunction: "sdr"}
+}
+
+func rc6Audio() protocol.AudioProfile {
+	return protocol.AudioProfile{Codec: "opus", SampleRateHz: 48000, Channels: 2, ChannelLayout: "stereo", PacketDurationMs: 5}
+}
+
+func rc6Capability(codecs ...string) protocol.CapabilityProfile {
+	videos := make([]protocol.VideoProfile, len(codecs))
+	for index, codec := range codecs { videos[index] = rc6Video(codec) }
+	return protocol.CapabilityProfile{Transport: "quic-tls13", Framing: "datagram-v1", Media: "encoded", SourceRateControl: "server", VideoProfiles: videos, AudioProfiles: []protocol.AudioProfile{rc6Audio()}}
+}
+
+func rc6Descriptor(codec string) protocol.SelectedSessionDescriptor {
+	return protocol.SelectedSessionDescriptor{VideoProfile: rc6Video(codec), AudioProfile: rc6Audio(), DisplayMode: protocol.DisplayMode{ResolutionWidth: 1920, ResolutionHeight: 1080, Fps: 60}, BitrateTargetKbps: 20000, BitrateMaximumKbps: 40000, Adjustment: protocol.SessionAdjustment{DisplayReason: "none", BitrateReason: "none"}, MediaTimestampBasis: "gateway-send-wall-clock-ms"}
+}
+
 func TestDeviceRegistrationProofTranscriptIsCanonicalAndStrict(t *testing.T) {
 	serverID, _ := hex.DecodeString("00112233445566778899aabbccddeeff")
 	principalID, _ := hex.DecodeString("102132435465768798a9bacbdcedfe0f")
@@ -51,7 +69,7 @@ func TestDeviceRegistrationProofTranscriptIsCanonicalAndStrict(t *testing.T) {
 }

 func TestManifestRejectsForbiddenAndUnknownFields(t *testing.T) {
-	valid := `{"version":"1","purpose":"launch","session_id":"session-1","reconnect_sequence":0,"gateway":{"id":"gateway-1","addresses":["gateway.control.test:443"],"public_identity":"gateway.control.test"},"tunnel":{"versions":["verse-gateway-v1/1"],"features":["control.v1"]},"profile":{"id":"standard","bounds":{"minimum_kbps":1,"target_kbps":2,"maximum_kbps":3}},"grant":{"opaque_value":"opaque-one-time-grant-value-with-at-least-43-bytes","expires_at":"2099-01-01T00:00:00Z","audience":"versevdi-gateway"},"correlation_id":"correlation-1"}`
+	valid := `{"version":"1","purpose":"launch","session_id":"session-1","reconnect_sequence":0,"gateway":{"id":"gateway-1","addresses":["gateway.control.test:443"],"public_identity":"gateway.control.test"},"tunnel":{"versions":["verse-gateway-v1/1"],"features":["control.v1"]},"profile":{"id":"standard","bounds":{"minimum_kbps":1,"target_kbps":2,"maximum_kbps":3}},"grant":{"opaque_value":"opaque-one-time-grant-value-with-at-least-43-bytes","expires_at":"2099-01-01T00:00:00Z","audience":"versevdi-gateway"},"correlation_id":"correlation-1","selected_descriptor":{"video_profile":{"codec":"h264","bit_depth":8,"chroma_subsampling":"4:2:0","color_space":"bt709-limited","transfer_function":"sdr"},"audio_profile":{"codec":"opus","sample_rate_hz":48000,"channels":2,"channel_layout":"stereo","packet_duration_ms":5},"display_mode":{"resolution_width":1920,"resolution_height":1080,"fps":60},"bitrate_target_kbps":20000,"bitrate_maximum_kbps":40000,"adjustment":{"display_reason":"none","bitrate_reason":"none"},"media_timestamp_basis":"gateway-send-wall-clock-ms"}}`
 	manifest, err := protocol.DecodeConnectionManifest([]byte(valid))
 	if err != nil || manifest.Gateway.ID != "gateway-1" {
 		t.Fatalf("valid manifest = %+v, err = %v", manifest, err)
@@ -83,6 +101,7 @@ func TestDisplayModeIsOptionalStrictAndBounded(t *testing.T) {

 	request := protocol.SessionRequest{
 		ClientDeviceID: "device-1", DeviceKeyID: "key-1", PoolID: "pool-1", IdempotencyKey: "request-1",
+		VideoProfiles: []protocol.VideoProfile{rc6Video("h264")}, BitratePreference: protocol.BitratePreference{Mode: "auto"},
 	}
 	legacy, err := protocol.EncodeSessionRequest(request)
 	if err != nil {
@@ -140,7 +159,7 @@ func TestSessionRequestRejectsClientPolicySnapshot(t *testing.T) {
 	if protocol.CurrentWireVersion != "2" || protocol.NMinus1WireVersion != "1" || protocol.NMinus2WireVersion != "0" {
 		t.Fatalf("wire compatibility = current %q, n-1 %q, n-2 %q", protocol.CurrentWireVersion, protocol.NMinus1WireVersion, protocol.NMinus2WireVersion)
 	}
-	request := `{"client_device_id":"device-1","device_key_id":"key-1","pool_id":"pool-1","idempotency_key":"request-1"}`
+	request := `{"client_device_id":"device-1","device_key_id":"key-1","pool_id":"pool-1","idempotency_key":"request-1","video_profiles":[{"codec":"h264","bit_depth":8,"chroma_subsampling":"4:2:0","color_space":"bt709-limited","transfer_function":"sdr"}],"bitrate_preference":{"mode":"auto"}}`
 	if _, err := protocol.DecodeSessionRequest([]byte(request)); err != nil {
 		t.Fatalf("policy-free SessionRequest rejected: %v", err)
 	}
@@ -225,7 +244,7 @@ func TestGeneratedDecodersRejectMissingRequiredFieldsAndTrailingValues(t *testin
 }

 func TestGatewayContractsRejectUnknownVersionsAndFields(t *testing.T) {
-	registration := `{"version":"1","gateway_id":"gateway-1","instance_identity":"instance-1","certificate_identity":"cert-1","public_identity":"public-1","address":"gateway.test:443","provider_identity":"apollo-provider-1","protocol_min_version":1,"protocol_max_version":1,"connection_capacity":8,"bandwidth_capacity_kbps":100000,"features":["datagram.media"],"capabilities":{"transport":"quic","framing":"datagram-v1","media":"encoded","audio":"encoded","source_rate_control":"server","client_decode":["h264-opus"]}}`
+	registration := `{"version":"1","gateway_id":"gateway-1","instance_identity":"instance-1","certificate_identity":"cert-1","public_identity":"public-1","address":"gateway.test:443","provider_identity":"apollo-provider-1","protocol_min_version":1,"protocol_max_version":1,"connection_capacity":8,"bandwidth_capacity_kbps":100000,"features":["datagram.media"],"capabilities":{"transport":"quic","framing":"datagram-v1","media":"encoded","source_rate_control":"server","video_profiles":[{"codec":"h264","bit_depth":8,"chroma_subsampling":"4:2:0","color_space":"bt709-limited","transfer_function":"sdr"}],"audio_profiles":[{"codec":"opus","sample_rate_hz":48000,"channels":2,"channel_layout":"stereo","packet_duration_ms":5}]}}`
 	if _, err := protocol.DecodeGatewayRegistration([]byte(registration)); err != nil {
 		t.Fatalf("valid gateway registration rejected: %v", err)
 	}
@@ -244,7 +263,7 @@ func TestGatewayContractsRejectUnknownVersionsAndFields(t *testing.T) {
 }

 func TestGatewayRegistrationRejectsInvertedProtocolBounds(t *testing.T) {
-	registration := `{"version":"1","gateway_id":"gateway-1","instance_identity":"instance-1","certificate_identity":"cert-1","public_identity":"public-1","address":"gateway.test:443","provider_identity":"apollo-provider-1","protocol_min_version":2,"protocol_max_version":1,"connection_capacity":8,"bandwidth_capacity_kbps":100000,"features":["datagram.media"],"capabilities":{"transport":"quic","framing":"datagram-v1","media":"encoded","audio":"encoded","source_rate_control":"server","client_decode":["h264-opus"]}}`
+	registration := `{"version":"1","gateway_id":"gateway-1","instance_identity":"instance-1","certificate_identity":"cert-1","public_identity":"public-1","address":"gateway.test:443","provider_identity":"apollo-provider-1","protocol_min_version":2,"protocol_max_version":1,"connection_capacity":8,"bandwidth_capacity_kbps":100000,"features":["datagram.media"],"capabilities":{"transport":"quic","framing":"datagram-v1","media":"encoded","source_rate_control":"server","video_profiles":[{"codec":"h264","bit_depth":8,"chroma_subsampling":"4:2:0","color_space":"bt709-limited","transfer_function":"sdr"}],"audio_profiles":[{"codec":"opus","sample_rate_hz":48000,"channels":2,"channel_layout":"stereo","packet_duration_ms":5}]}}`
 	if _, err := protocol.DecodeGatewayRegistration([]byte(registration)); err == nil {
 		t.Fatal("DecodeGatewayRegistration accepted inverted protocol bounds")
 	}
@@ -267,12 +286,12 @@ func TestGatewayHeartbeatCarriesBoundedObservedTelemetry(t *testing.T) {
 }

 func TestCapabilityIntersectionRejectsNoOverlap(t *testing.T) {
-	first := protocol.CapabilityProfile{Transport: "quic-tls13", Framing: "datagram-v1", Media: "encoded", Audio: "encoded", SourceRateControl: "server", ClientDecode: []string{"h264-opus"}}
+	first := rc6Capability("h264")
 	if got, err := protocol.IntersectCapabilityProfiles(first, first); err != nil || !reflect.DeepEqual(got, first) {
 		t.Fatalf("IntersectCapabilityProfiles matching profiles = %+v, %v", got, err)
 	}
 	second := first
-	second.ClientDecode = []string{"hevc-opus"}
+	second.VideoProfiles = []protocol.VideoProfile{rc6Video("hevc")}
 	if _, err := protocol.IntersectCapabilityProfiles(first, second); err == nil {
 		t.Fatal("IntersectCapabilityProfiles accepted profiles without a common codec profile")
 	}
@@ -280,31 +299,31 @@ func TestCapabilityIntersectionRejectsNoOverlap(t *testing.T) {

 func TestCapabilityIntersectionSelectsRegisteredOrderedProfiles(t *testing.T) {
 	gateway := protocol.CapabilityProfile{
-		Transport: "quic-tls13", Framing: "datagram-v1", Media: "encoded", Audio: "encoded",
-		SourceRateControl: "server", ClientDecode: []string{"hevc-opus", "h264-opus"},
+		Transport: "quic-tls13", Framing: "datagram-v1", Media: "encoded",
+		SourceRateControl: "server", VideoProfiles: []protocol.VideoProfile{rc6Video("hevc"), rc6Video("h264")}, AudioProfiles: []protocol.AudioProfile{rc6Audio()},
 	}
 	h264Client := gateway
-	h264Client.ClientDecode = []string{"h264-opus"}
+	h264Client.VideoProfiles = []protocol.VideoProfile{rc6Video("h264")}
 	selected, err := protocol.IntersectCapabilityProfiles(gateway, h264Client)
-	if err != nil || !reflect.DeepEqual(selected.ClientDecode, []string{"h264-opus"}) {
+	if err != nil || !reflect.DeepEqual(selected.VideoProfiles, []protocol.VideoProfile{rc6Video("h264")}) {
 		t.Fatalf("H.264 profile intersection = %+v, %v", selected, err)
 	}
 	hevcClient := gateway
-	hevcClient.ClientDecode = []string{"hevc-opus"}
+	hevcClient.VideoProfiles = []protocol.VideoProfile{rc6Video("hevc")}
 	selected, err = protocol.IntersectCapabilityProfiles(gateway, hevcClient)
-	if err != nil || !reflect.DeepEqual(selected.ClientDecode, []string{"hevc-opus"}) {
+	if err != nil || !reflect.DeepEqual(selected.VideoProfiles, []protocol.VideoProfile{rc6Video("hevc")}) {
 		t.Fatalf("HEVC profile intersection = %+v, %v", selected, err)
 	}
 	noOverlap := gateway
-	noOverlap.ClientDecode = []string{"h264-opus"}
+	noOverlap.VideoProfiles = []protocol.VideoProfile{rc6Video("h264")}
 	if _, err := protocol.IntersectCapabilityProfiles(noOverlap, hevcClient); err == nil {
 		t.Fatal("intersection accepted registered profiles without overlap")
 	}
-	for _, invalid := range [][]string{{"h264-hevc-opus"}, {"h264-opus", "h264-opus"}} {
+	for _, invalid := range [][]protocol.VideoProfile{{{Codec: "vp9", BitDepth: 8, ChromaSubsampling: "4:2:0", ColorSpace: "bt709-limited", TransferFunction: "sdr"}}, {rc6Video("h264"), rc6Video("h264")}} {
 		profile := gateway
-		profile.ClientDecode = invalid
+		profile.VideoProfiles = invalid
 		if err := profile.Validate(); err == nil {
-			t.Fatalf("CapabilityProfile accepted invalid registered profile set %q", invalid)
+			t.Fatalf("CapabilityProfile accepted invalid registered profile set %+v", invalid)
 		}
 	}
 }
@@ -312,7 +331,7 @@ func TestCapabilityIntersectionSelectsRegisteredOrderedProfiles(t *testing.T) {
 func TestCapabilityProfileRequiresRegisteredFraming(t *testing.T) {
 	valid := protocol.CapabilityProfile{
 		Transport: "quic-tls13", Framing: "datagram-v2", Media: "encoded",
-		Audio: "encoded", SourceRateControl: "server", ClientDecode: []string{"h264-opus"},
+		SourceRateControl: "server", VideoProfiles: []protocol.VideoProfile{rc6Video("h264")}, AudioProfiles: []protocol.AudioProfile{rc6Audio()},
 	}
 	if err := valid.Validate(); err != nil {
 		t.Fatalf("registered datagram-v2 rejected: %v", err)
@@ -329,8 +348,8 @@ func TestTunnelAdmissionRequiresDeviceSignature(t *testing.T) {
 		Version: "1", SessionID: "session-1", GatewayID: "gateway-1", Audience: "versevdi-gateway",
 		Grant: "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789-_", ReconnectSequence: 0,
 		ClientNonce: "0123456789abcdef", Capabilities: protocol.CapabilityProfile{
-			Transport: "quic-tls13", Framing: "datagram-v1", Media: "encoded", Audio: "encoded",
-			SourceRateControl: "server", ClientDecode: []string{"h264-opus"},
+			Transport: "quic-tls13", Framing: "datagram-v1", Media: "encoded",
+			SourceRateControl: "server", VideoProfiles: []protocol.VideoProfile{rc6Video("h264")}, AudioProfiles: []protocol.AudioProfile{rc6Audio()},
 		},
 	}
 	if _, err := protocol.EncodeTunnelAdmissionRequest(request); err == nil {
@@ -343,18 +362,18 @@ func TestTunnelAdmissionTranscriptIsDomainSeparatedAndLengthDelimited(t *testing
 		Version: "1", SessionID: "session", GatewayID: "gateway", Audience: "audience",
 		Grant: strings.Repeat("g", 43), ReconnectSequence: 0, ClientNonce: strings.Repeat("n", 16),
 		DeviceSignature: strings.Repeat("s", 86), Capabilities: protocol.CapabilityProfile{
-			Transport: "quic-tls13", Framing: "datagram-v1", Media: "encoded", Audio: "encoded",
-			SourceRateControl: "server", ClientDecode: []string{"h264-opus"},
+			Transport: "quic-tls13", Framing: "datagram-v1", Media: "encoded",
+			SourceRateControl: "server", VideoProfiles: []protocol.VideoProfile{rc6Video("h264")}, AudioProfiles: []protocol.AudioProfile{rc6Audio()},
 		},
 	}
-	want := "versevdi/tunnel-admission/v17:session7:gateway8:audience43:" + strings.Repeat("g", 43) + "1:016:" + strings.Repeat("n", 16) + "10:quic-tls1311:datagram-v17:encoded7:encoded6:server1:19:h264-opus"
+	want := "versevdi/tunnel-admission/v17:session7:gateway8:audience43:" + strings.Repeat("g", 43) + "1:016:" + strings.Repeat("n", 16) + "10:quic-tls1311:datagram-v17:encoded6:server1:11:14:h2641:85:4:2:013:bt709-limited3:sdr4:opus5:480001:26:stereo1:5"
 	if got := string(request.DeviceAdmissionTranscript()); got != want {
 		t.Fatalf("DeviceAdmissionTranscript() = %q, want %q", got, want)
 	}
 }

 func TestSessionAuthorityRejectsProviderRoute(t *testing.T) {
-	valid := `{"version":"1","session_id":"session-1","gateway_id":"gateway-1","audience":"versevdi-gateway","reconnect_sequence":0,"expires_at":"2099-01-01T00:00:00Z","capabilities":{"transport":"quic","framing":"datagram-v1","media":"encoded","audio":"encoded","source_rate_control":"server","client_decode":["h264-opus"]},"provider_profile":"apollo","provider_identity":"provider-1"}`
+	valid := `{"version":"1","session_id":"session-1","gateway_id":"gateway-1","audience":"versevdi-gateway","reconnect_sequence":0,"expires_at":"2099-01-01T00:00:00Z","capabilities":{"transport":"quic","framing":"datagram-v1","media":"encoded","source_rate_control":"server","video_profiles":[{"codec":"h264","bit_depth":8,"chroma_subsampling":"4:2:0","color_space":"bt709-limited","transfer_function":"sdr"}],"audio_profiles":[{"codec":"opus","sample_rate_hz":48000,"channels":2,"channel_layout":"stereo","packet_duration_ms":5}]},"provider_profile":"apollo","provider_identity":"provider-1","selected_descriptor":{"video_profile":{"codec":"h264","bit_depth":8,"chroma_subsampling":"4:2:0","color_space":"bt709-limited","transfer_function":"sdr"},"audio_profile":{"codec":"opus","sample_rate_hz":48000,"channels":2,"channel_layout":"stereo","packet_duration_ms":5},"display_mode":{"resolution_width":1920,"resolution_height":1080,"fps":60},"bitrate_target_kbps":20000,"bitrate_maximum_kbps":40000,"adjustment":{"display_reason":"none","bitrate_reason":"none"},"media_timestamp_basis":"gateway-send-wall-clock-ms"}}`
 	if _, err := protocol.DecodeSessionAuthority([]byte(valid)); err != nil {
 		t.Fatalf("valid session authority rejected: %v", err)
 	}
@@ -367,9 +386,10 @@ func TestClientSessionAuthorityIsStrictAndProviderFree(t *testing.T) {
 	authority := protocol.ClientSessionAuthority{
 		Version: "1", SessionID: "session-1", GatewayID: "gateway-1", Audience: "versevdi-gateway",
 		ReconnectSequence: 2, ExpiresAt: "2099-01-01T00:00:00Z", Capabilities: protocol.CapabilityProfile{
-			Transport: "quic-tls13", Framing: "datagram-v1", Media: "encoded", Audio: "encoded",
-			SourceRateControl: "server", ClientDecode: []string{"h264-opus"},
+			Transport: "quic-tls13", Framing: "datagram-v1", Media: "encoded",
+			SourceRateControl: "server", VideoProfiles: []protocol.VideoProfile{rc6Video("h264")}, AudioProfiles: []protocol.AudioProfile{rc6Audio()},
 		},
+		SelectedDescriptor: rc6Descriptor("h264"),
 	}
 	encoded, err := protocol.EncodeClientSessionAuthority(authority)
 	if err != nil {
@@ -381,7 +401,7 @@ func TestClientSessionAuthorityIsStrictAndProviderFree(t *testing.T) {
 	}
 	wantFields := map[string]bool{
 		"version": true, "session_id": true, "gateway_id": true, "audience": true,
-		"reconnect_sequence": true, "expires_at": true, "capabilities": true,
+		"reconnect_sequence": true, "expires_at": true, "capabilities": true, "selected_descriptor": true,
 	}
 	if len(fields) != len(wantFields) {
 		t.Fatalf("encoded client authority fields = %v; want exactly %v", fields, wantFields)
@@ -399,7 +419,7 @@ func TestClientSessionAuthorityIsStrictAndProviderFree(t *testing.T) {
 		t.Fatalf("DecodeClientSessionAuthority() = %+v, %v; want %+v", decoded, err, authority)
 	}

-	for _, field := range []string{"version", "session_id", "gateway_id", "audience", "reconnect_sequence", "expires_at", "capabilities"} {
+	for _, field := range []string{"version", "session_id", "gateway_id", "audience", "reconnect_sequence", "expires_at", "capabilities", "selected_descriptor"} {
 		missing := make(map[string]json.RawMessage, len(fields)-1)
 		for key, value := range fields {
 			if key != field {
@@ -439,7 +459,7 @@ func TestClientSessionAuthorityIsStrictAndProviderFree(t *testing.T) {
 }

 func TestProviderSessionWorkIsStrictAndSessionBound(t *testing.T) {
-	valid := `{"version":"1","session_id":"session-1","gateway_id":"gateway-1","reconnect_sequence":0,"expires_at":"2099-01-01T00:00:00Z","provider_profile":"apollo","provider_identity":"provider-1","policy_version_id":"policy-1","stream_policy":{"resolution_width":2560,"resolution_height":1440,"fps":120,"codec":"HEVC","bitrate_kbps":40000,"audio_enabled":true},"application_id":"42","client_id":"paired-client-1","management_host":"apollo.test","management_port":47990,"stream_host":"apollo.test","stream_port":47984,"client_certificate_pem":"certificate","client_private_key_pem":"private-key","server_certificate_pem":"server-certificate","clipboard_policy":{"client_to_provider_enabled":false,"provider_to_client_enabled":false,"max_text_bytes":65536,"max_updates_per_minute":30},"provider_application_termination_allowed":false}`
+	valid := `{"version":"1","session_id":"session-1","gateway_id":"gateway-1","reconnect_sequence":0,"expires_at":"2099-01-01T00:00:00Z","provider_profile":"apollo","provider_identity":"provider-1","policy_version_id":"policy-1","stream_policy":{"video_profile":{"codec":"hevc","bit_depth":8,"chroma_subsampling":"4:2:0","color_space":"bt709-limited","transfer_function":"sdr"},"audio_profile":{"codec":"opus","sample_rate_hz":48000,"channels":2,"channel_layout":"stereo","packet_duration_ms":5},"display_mode":{"resolution_width":2560,"resolution_height":1440,"fps":120},"bitrate_target_kbps":40000,"bitrate_maximum_kbps":50000},"application_id":"42","client_id":"paired-client-1","management_host":"apollo.test","management_port":47990,"stream_host":"apollo.test","stream_port":47984,"client_certificate_pem":"certificate","client_private_key_pem":"private-key","server_certificate_pem":"server-certificate","clipboard_policy":{"client_to_provider_enabled":false,"provider_to_client_enabled":false,"max_text_bytes":65536,"max_updates_per_minute":30},"provider_application_termination_allowed":false}`
 	if _, err := protocol.DecodeProviderSessionWork([]byte(valid)); err != nil {
 		t.Fatalf("valid provider work rejected: %v", err)
 	}
@@ -450,10 +470,10 @@ func TestProviderSessionWorkIsStrictAndSessionBound(t *testing.T) {
 		t.Fatal("provider work accepted missing clipboard policy")
 	}
 	for _, invalid := range []string{
-		strings.Replace(valid, `,"stream_policy":{"resolution_width":2560,"resolution_height":1440,"fps":120,"codec":"HEVC","bitrate_kbps":40000,"audio_enabled":true}`, "", 1),
+		strings.Replace(valid, `,"stream_policy":{"video_profile":{"codec":"hevc","bit_depth":8,"chroma_subsampling":"4:2:0","color_space":"bt709-limited","transfer_function":"sdr"},"audio_profile":{"codec":"opus","sample_rate_hz":48000,"channels":2,"channel_layout":"stereo","packet_duration_ms":5},"display_mode":{"resolution_width":2560,"resolution_height":1440,"fps":120},"bitrate_target_kbps":40000,"bitrate_maximum_kbps":50000}`, "", 1),
 		strings.Replace(valid, `"fps":120`, `"fps":241`, 1),
-		strings.Replace(valid, `"codec":"HEVC"`, `"codec":"VP9"`, 1),
-		strings.Replace(valid, `"audio_enabled":true`, `"audio_enabled":true,"unknown":false`, 1),
+		strings.Replace(valid, `"codec":"hevc"`, `"codec":"vp9"`, 1),
+		strings.Replace(valid, `"packet_duration_ms":5`, `"packet_duration_ms":5,"unknown":false`, 1),
 	} {
 		if _, err := protocol.DecodeProviderSessionWork([]byte(invalid)); err == nil {
 			t.Fatalf("provider work accepted invalid stream policy: %s", invalid)
@@ -0,0 +1,260 @@
+package protocol_test
+
+import (
+	"os"
+	"reflect"
+	"strings"
+	"testing"
+
+	protocol "git.sechmachine.io.vn/sechmachine/VerseVDI-Protocol/gen/go/protocol"
+)
+
+func TestRC6GeneratedContractsHaveFrozenExactShapes(t *testing.T) {
+	tests := []struct {
+		value  any
+		fields []string
+	}{
+		{protocol.VideoProfile{}, []string{"Codec", "BitDepth", "ChromaSubsampling", "ColorSpace", "TransferFunction"}},
+		{protocol.AudioProfile{}, []string{"Codec", "SampleRateHz", "Channels", "ChannelLayout", "PacketDurationMs"}},
+		{protocol.BitratePreference{}, []string{"Mode", "TargetKbps"}},
+		{protocol.SessionQualityLimits{}, []string{"PolicyVersionID", "PolicyDisplayLimit", "SelectableDisplayMaximum", "DisplayLimitOverride", "BitrateMinimumKbps", "BitrateTargetKbps", "BitrateMaximumKbps"}},
+		{protocol.SessionAdjustment{}, []string{"DisplayReason", "BitrateReason"}},
+		{protocol.SelectedSessionDescriptor{}, []string{"VideoProfile", "AudioProfile", "DisplayMode", "BitrateTargetKbps", "BitrateMaximumKbps", "Adjustment", "MediaTimestampBasis"}},
+	}
+	for _, test := range tests {
+		typeOf := reflect.TypeOf(test.value)
+		if typeOf.NumField() != len(test.fields) {
+			t.Fatalf("%s field count = %d, want %d", typeOf.Name(), typeOf.NumField(), len(test.fields))
+		}
+		for index, field := range test.fields {
+			if typeOf.Field(index).Name != field {
+				t.Fatalf("%s field %d = %s, want %s", typeOf.Name(), index, typeOf.Field(index).Name, field)
+			}
+		}
+	}
+}
+
+func TestRC6ProfileValidationAndOrderedIntersection(t *testing.T) {
+	h264 := protocol.VideoProfile{Codec: "h264", BitDepth: 8, ChromaSubsampling: "4:2:0", ColorSpace: "bt709-limited", TransferFunction: "sdr"}
+	hevc := h264
+	hevc.Codec = "hevc"
+	audio := protocol.AudioProfile{Codec: "opus", SampleRateHz: 48000, Channels: 2, ChannelLayout: "stereo", PacketDurationMs: 5}
+	first := protocol.CapabilityProfile{Transport: "quic-tls13", Framing: "datagram-v2", Media: "encoded", SourceRateControl: "server", VideoProfiles: []protocol.VideoProfile{h264, hevc}, AudioProfiles: []protocol.AudioProfile{audio}}
+	second := first
+	second.VideoProfiles = []protocol.VideoProfile{hevc, h264}
+	selected, err := protocol.IntersectCapabilityProfiles(first, second)
+	if err != nil || !reflect.DeepEqual(selected.VideoProfiles, []protocol.VideoProfile{h264, hevc}) {
+		t.Fatalf("ordered intersection = %+v, %v", selected.VideoProfiles, err)
+	}
+	duplicate := first
+	duplicate.VideoProfiles = []protocol.VideoProfile{h264, h264}
+	if duplicate.Validate() == nil {
+		t.Fatal("CapabilityProfile accepted duplicate video profiles")
+	}
+	invalid := h264
+	invalid.BitDepth = 10
+	if invalid.Validate() == nil {
+		t.Fatal("VideoProfile accepted a non-RC6 bit depth")
+	}
+}
+
+func TestRC6StrictDecodeRejectsLegacyAndMalformedBodies(t *testing.T) {
+	for name, test := range map[string]struct {
+		payload []byte
+		decode  func([]byte) error
+	}{
+		"opaque capability":   {[]byte(`{"transport":"quic-tls13","framing":"datagram-v2","media":"encoded","audio":"encoded","source_rate_control":"server","client_decode":["h264-opus"]}`), func(raw []byte) error { _, err := protocol.DecodeCapabilityProfile(raw); return err }},
+		"old session request": {[]byte(`{"client_device_id":"device-1","device_key_id":"key-1","pool_id":"pool-1","idempotency_key":"request-1"}`), func(raw []byte) error { _, err := protocol.DecodeSessionRequest(raw); return err }},
+		"old provider policy": {[]byte(`{"resolution_width":1920,"resolution_height":1080,"fps":60,"codec":"H264","bitrate_kbps":20000,"audio_enabled":true}`), func(raw []byte) error { _, err := protocol.DecodeProviderStreamPolicy(raw); return err }},
+		"unknown field":       {[]byte(`{"mode":"explicit","target_kbps":1000,"unknown":true}`), func(raw []byte) error { _, err := protocol.DecodeBitratePreference(raw); return err }},
+		"duplicate key":       {[]byte(`{"mode":"explicit","mode":"auto","target_kbps":1000}`), func(raw []byte) error { _, err := protocol.DecodeBitratePreference(raw); return err }},
+		"trailing JSON":       {[]byte(`{"mode":"explicit","target_kbps":1000} {}`), func(raw []byte) error { _, err := protocol.DecodeBitratePreference(raw); return err }},
+	} {
+		if err := test.decode(test.payload); err == nil {
+			t.Fatalf("RC6 accepted %s", name)
+		}
+	}
+}
+
+func TestRC6BitratePreferenceTaggedBounds(t *testing.T) {
+	for _, valid := range []protocol.BitratePreference{{Mode: "auto"}, {Mode: "explicit", TargetKbps: int64Pointer(100)}, {Mode: "explicit", TargetKbps: int64Pointer(1_000_000)}} {
+		if err := valid.Validate(); err != nil {
+			t.Fatalf("valid preference %+v rejected: %v", valid, err)
+		}
+	}
+	for _, invalid := range []protocol.BitratePreference{{Mode: "auto", TargetKbps: int64Pointer(100)}, {Mode: "explicit"}, {Mode: "explicit", TargetKbps: int64Pointer(99)}, {Mode: "explicit", TargetKbps: int64Pointer(1_000_001)}} {
+		if invalid.Validate() == nil {
+			t.Fatalf("invalid preference %+v accepted", invalid)
+		}
+	}
+}
+
+func TestRC6GatewayQualityDiscoveryAndLeaseFencing(t *testing.T) {
+	operationID := "12345678-1234-1234-1234-123456789abc"
+	revision := int64(7)
+	leaseGeneration := int64(3)
+	currentRevision := int64(6)
+
+	poll := protocol.GatewayQualityWorkRequest{Version: "1", SessionID: "session-1", GatewayID: "gateway-1", ReconnectSequence: 2, Acquisition: "poll"}
+	if err := poll.Validate(); err != nil {
+		t.Fatalf("session-bound lost-prompt poll rejected: %v", err)
+	}
+	prompt := poll
+	prompt.Acquisition = "prompt"
+	prompt.OperationID = operationID
+	prompt.Revision = &revision
+	if err := prompt.Validate(); err != nil {
+		t.Fatalf("prompt-bound acquisition rejected: %v", err)
+	}
+	observation := prompt
+	observation.Acquisition = "observation"
+	observation.LeaseGeneration = &leaseGeneration
+	observation.CurrentAppliedRevision = &currentRevision
+	if err := observation.Validate(); err != nil {
+		t.Fatalf("lease-bound applied-revision observation rejected: %v", err)
+	}
+
+	for name, invalid := range map[string]protocol.GatewayQualityWorkRequest{
+		"poll with unknown coordinates": prompt,
+		"prompt missing revision":       {Version: "1", SessionID: "session-1", GatewayID: "gateway-1", Acquisition: "prompt", OperationID: operationID},
+		"observation missing lease":     {Version: "1", SessionID: "session-1", GatewayID: "gateway-1", Acquisition: "observation", OperationID: operationID, Revision: &revision, CurrentAppliedRevision: &currentRevision},
+	} {
+		if name == "poll with unknown coordinates" {
+			invalid.Acquisition = "poll"
+		}
+		if invalid.Validate() == nil {
+			t.Fatalf("accepted invalid %s: %+v", name, invalid)
+		}
+	}
+
+	stopPoll := protocol.GatewayStopWorkRequest{Version: "1", SessionID: "session-1", GatewayID: "gateway-1", ReconnectSequence: 2, Acquisition: "poll"}
+	if err := stopPoll.Validate(); err != nil {
+		t.Fatalf("session-bound Stop poll rejected: %v", err)
+	}
+	stopPrompt := stopPoll
+	stopPrompt.Acquisition = "prompt"
+	stopPrompt.OperationID = operationID
+	if err := stopPrompt.Validate(); err != nil {
+		t.Fatalf("prompt-bound Stop acquisition rejected: %v", err)
+	}
+	stopPoll.OperationID = operationID
+	if stopPoll.Validate() == nil {
+		t.Fatal("Stop poll accepted unknown operation coordinates")
+	}
+}
+
+func TestRC6GatewayQualityAckHasUnambiguousObservation(t *testing.T) {
+	revision := int64(7)
+	prior := int64(6)
+	base := protocol.GatewayQualityAck{
+		Version: "1", SessionID: "session-1", GatewayID: "gateway-1", ReconnectSequence: 2,
+		OperationID: "12345678-1234-1234-1234-123456789abc", Revision: revision, LeaseGeneration: 3,
+	}
+	for _, valid := range []protocol.GatewayQualityAck{
+		func() protocol.GatewayQualityAck {
+			value := base
+			value.Outcome = "applied"
+			value.CurrentAppliedRevision = &revision
+			return value
+		}(),
+		func() protocol.GatewayQualityAck {
+			value := base
+			value.Outcome = "proven_prior"
+			value.CurrentAppliedRevision = &prior
+			return value
+		}(),
+		func() protocol.GatewayQualityAck { value := base; value.Outcome = "unknown"; return value }(),
+	} {
+		if err := valid.Validate(); err != nil {
+			t.Fatalf("valid quality acknowledgement rejected: %+v: %v", valid, err)
+		}
+	}
+	for _, invalid := range []protocol.GatewayQualityAck{
+		func() protocol.GatewayQualityAck {
+			value := base
+			value.Outcome = "applied"
+			value.CurrentAppliedRevision = &prior
+			return value
+		}(),
+		func() protocol.GatewayQualityAck {
+			value := base
+			value.Outcome = "proven_prior"
+			value.CurrentAppliedRevision = &revision
+			return value
+		}(),
+		func() protocol.GatewayQualityAck {
+			value := base
+			value.Outcome = "unknown"
+			value.CurrentAppliedRevision = &prior
+			return value
+		}(),
+		func() protocol.GatewayQualityAck {
+			value := base
+			value.Outcome = "unknown"
+			value.LeaseGeneration = 0
+			return value
+		}(),
+	} {
+		if invalid.Validate() == nil {
+			t.Fatalf("contradictory or unfenced quality acknowledgement accepted: %+v", invalid)
+		}
+	}
+}
+
+func TestRC6JSONFixturesAndCanonicalOperationFields(t *testing.T) {
+	validFixtures := map[string]func([]byte) error{
+		"../../fixtures/valid/session-request.json":             func(raw []byte) error { _, err := protocol.DecodeSessionRequest(raw); return err },
+		"../../fixtures/valid/selected-session-descriptor.json": func(raw []byte) error { _, err := protocol.DecodeSelectedSessionDescriptor(raw); return err },
+		"../../fixtures/valid/session-quality-limits.json":      func(raw []byte) error { _, err := protocol.DecodeSessionQualityLimits(raw); return err },
+		"../../fixtures/valid/gateway-quality-poll.json":        func(raw []byte) error { _, err := protocol.DecodeGatewayQualityWorkRequest(raw); return err },
+		"../../fixtures/valid/gateway-quality-ack-applied.json": func(raw []byte) error { _, err := protocol.DecodeGatewayQualityAck(raw); return err },
+	}
+	for path, decode := range validFixtures {
+		raw, err := os.ReadFile(path)
+		if err != nil {
+			t.Fatalf("read valid fixture %s: %v", path, err)
+		}
+		if err := decode(raw); err != nil {
+			t.Fatalf("valid fixture %s rejected: %v", path, err)
+		}
+	}
+	invalidFixtures := map[string]func([]byte) error{
+		"../../fixtures/invalid/capability-rc5-opaque.json":                      func(raw []byte) error { _, err := protocol.DecodeCapabilityProfile(raw); return err },
+		"../../fixtures/invalid/session-request-rc5.json":                        func(raw []byte) error { _, err := protocol.DecodeSessionRequest(raw); return err },
+		"../../fixtures/invalid/provider-stream-policy-rc5.json":                 func(raw []byte) error { _, err := protocol.DecodeProviderStreamPolicy(raw); return err },
+		"../../fixtures/invalid/video-profile-unknown.json":                      func(raw []byte) error { _, err := protocol.DecodeVideoProfile(raw); return err },
+		"../../fixtures/invalid/bitrate-preference-auto-target.json":             func(raw []byte) error { _, err := protocol.DecodeBitratePreference(raw); return err },
+		"../../fixtures/invalid/selected-session-descriptor-provider-field.json": func(raw []byte) error { _, err := protocol.DecodeSelectedSessionDescriptor(raw); return err },
+		"../../fixtures/invalid/gateway-quality-poll-coordinates.json":           func(raw []byte) error { _, err := protocol.DecodeGatewayQualityWorkRequest(raw); return err },
+		"../../fixtures/invalid/gateway-quality-ack-contradictory.json":          func(raw []byte) error { _, err := protocol.DecodeGatewayQualityAck(raw); return err },
+		"../../fixtures/invalid/gateway-quality-ack-uppercase-uuid.json":         func(raw []byte) error { _, err := protocol.DecodeGatewayQualityAck(raw); return err },
+		"../../fixtures/invalid/gateway-quality-ack-zero-uuid.json":              func(raw []byte) error { _, err := protocol.DecodeGatewayQualityAck(raw); return err },
+		"../../fixtures/invalid/quality-operation-offset-time.json":              func(raw []byte) error { _, err := protocol.DecodeQualityChangeOperation(raw); return err },
+		"../../fixtures/invalid/quality-operation-noncanonical-fraction.json":    func(raw []byte) error { _, err := protocol.DecodeQualityChangeOperation(raw); return err },
+	}
+	for path, decode := range invalidFixtures {
+		raw, err := os.ReadFile(path)
+		if err != nil {
+			t.Fatal(err)
+		}
+		if decode(raw) == nil {
+			t.Fatalf("invalid fixture %s accepted", path)
+		}
+	}
+	validOperation := `{"operation_id":"12345678-1234-1234-1234-123456789abc","session_id":"session-1","revision":1,"state":"pending","requested_bitrate_preference":{"mode":"auto"},"effective_bitrate_kbps":20000,"governing_policy_version":"policy-1","session_version":1,"created_at":"2099-01-01T00:00:00Z","deadline_at":"2099-01-01T00:00:30Z","updated_at":"2099-01-01T00:00:00Z"}`
+	if _, err := protocol.DecodeQualityChangeOperation([]byte(validOperation)); err != nil {
+		t.Fatalf("valid quality operation rejected: %v", err)
+	}
+	for _, invalid := range []string{
+		strings.Replace(validOperation, "123456789abc", "123456789ABC", 1),
+		strings.Replace(validOperation, "12345678-1234-1234-1234-123456789abc", "00000000-0000-0000-0000-000000000000", 1),
+		strings.Replace(validOperation, "2099-01-01T00:00:00Z", "2099-01-01T00:00:00+00:00", 1),
+		strings.Replace(validOperation, `,"revision":1`, "", 1),
+	} {
+		if _, err := protocol.DecodeQualityChangeOperation([]byte(invalid)); err == nil {
+			t.Fatalf("invalid operation accepted: %s", invalid)
+		}
+	}
+}
+
+func int64Pointer(value int64) *int64 { return &value }
@@ -32,7 +32,17 @@ def main() -> int:
    expected = manifest.get("corpus_sha256")
    if not expected or actual != expected:
        raise ValueError(f"fixture corpus hash mismatch: {actual}")
-    print(f"Fixture corpus SHA256 {actual}")
+    json_paths = sorted(
+        path.relative_to(ROOT).as_posix()
+        for directory in (ROOT / "fixtures/valid", ROOT / "fixtures/invalid")
+        for path in directory.glob("*.json")
+    )
+    if json_paths != manifest.get("json_files"):
+        raise ValueError("JSON fixture manifest file list is stale")
+    json_actual = digest(json_paths)
+    if json_actual != manifest.get("json_corpus_sha256"):
+        raise ValueError(f"JSON fixture corpus hash mismatch: {json_actual}")
+    print(f"Fixture corpus SHA256 {actual}; JSON SHA256 {json_actual}")
    return 0


@@ -139,11 +139,15 @@ def go_validation(definition: dict[str, Any]) -> list[str]:
                )
            if prop.get("format") == "base64url":
                lines.append(f"\tif v.{field} != \"\" {{ if _, err := base64.RawURLEncoding.Strict().DecodeString(v.{field}); err != nil {{ violations = append(violations, FieldViolation{{Field: \"{prop_name}\", Code: \"invalid_format\"}}) }} }}")
+            if prop.get("format") == "uuid":
+                lines.append(f"\tif v.{field} != \"\" && !validCanonicalUUID(v.{field}) {{ violations = append(violations, FieldViolation{{Field: \"{prop_name}\", Code: \"invalid_uuid\"}}) }}")
        if prop.get("type") == "integer":
+            value = f"*v.{field}" if prop.get("x-optional-pointer") else f"v.{field}"
+            guard = f"v.{field} != nil && " if prop.get("x-optional-pointer") else ""
            if "minimum" in prop:
-                lines.append(f"\tif v.{field} != 0 && v.{field} < {prop['minimum']} {{ violations = append(violations, FieldViolation{{Field: \"{prop_name}\", Code: \"minimum\"}}) }}")
+                lines.append(f"\tif {guard}{value} != 0 && {value} < {prop['minimum']} {{ violations = append(violations, FieldViolation{{Field: \"{prop_name}\", Code: \"minimum\"}}) }}")
            if "maximum" in prop:
-                lines.append(f"\tif v.{field} > {prop['maximum']} {{ violations = append(violations, FieldViolation{{Field: \"{prop_name}\", Code: \"maximum\"}}) }}")
+                lines.append(f"\tif {guard}{value} > {prop['maximum']} {{ violations = append(violations, FieldViolation{{Field: \"{prop_name}\", Code: \"maximum\"}}) }}")
        if prop.get("type") == "array":
            if "minItems" in prop:
                lines.append(f"\tif len(v.{field}) < {prop['minItems']} {{ violations = append(violations, FieldViolation{{Field: \"{prop_name}\", Code: \"min_items\"}}) }}")
@@ -159,8 +163,8 @@ def go_validation(definition: dict[str, Any]) -> list[str]:
            if "enum" in items:
                allowed = " || ".join(f'item == "{value}"' for value in items["enum"])
                lines.append(f"\tfor _, item := range v.{field} {{ if !({allowed}) {{ violations = append(violations, FieldViolation{{Field: \"{prop_name}\", Code: \"invalid_item\"}}) }} }}")
-            if prop.get("uniqueItems") and items.get("type") == "string":
-                lines.append(f"\tfor index, item := range v.{field} {{ for prior := 0; prior < index; prior++ {{ if item == v.{field}[prior] {{ violations = append(violations, FieldViolation{{Field: \"{prop_name}\", Code: \"duplicate_item\"}}) }} }} }}")
+            if prop.get("uniqueItems"):
+                lines.append(f"\tfor index, item := range v.{field} {{ for prior := 0; prior < index; prior++ {{ if reflect.DeepEqual(item, v.{field}[prior]) {{ violations = append(violations, FieldViolation{{Field: \"{prop_name}\", Code: \"duplicate_item\"}}) }} }} }}")
            item_ref = ref_name(items)
            if item_ref:
                lines.append(f"\tfor index := range v.{field} {{ if err := v.{field}[index].Validate(); err != nil {{ violations = append(violations, FieldViolation{{Field: fmt.Sprintf(\"{prop_name}[%d]\", index), Code: \"invalid_item\"}}) }} }}")
@@ -173,6 +177,22 @@ def go_validation(definition: dict[str, Any]) -> list[str]:
                lines.append(f"\t{validation}")
    if name in {"AllocationPolicy", "ManifestBounds"}:
        lines.append("\tif v.MinimumKbps > v.TargetKbps || v.TargetKbps > v.MaximumKbps { violations = append(violations, FieldViolation{Field: \"bounds\", Code: \"invalid_order\"}) }")
+    if name == "SessionQualityLimits":
+        lines.append("\tif v.BitrateMinimumKbps > v.BitrateTargetKbps || v.BitrateTargetKbps > v.BitrateMaximumKbps { violations = append(violations, FieldViolation{Field: \"bitrate_bounds\", Code: \"invalid_order\"}) }")
+    if name in {"SelectedSessionDescriptor", "ProviderStreamPolicy"}:
+        lines.append("\tif v.BitrateTargetKbps > v.BitrateMaximumKbps { violations = append(violations, FieldViolation{Field: \"bitrate_bounds\", Code: \"invalid_order\"}) }")
+    if name == "BitratePreference":
+        lines.append("\tif v.Mode == \"auto\" && v.TargetKbps != nil || v.Mode == \"explicit\" && v.TargetKbps == nil { violations = append(violations, FieldViolation{Field: \"target_kbps\", Code: \"invalid_tagged_value\"}) }")
+    if name == "GatewayQualityWorkRequest":
+        lines.append("\tif v.Acquisition == \"poll\" && (v.OperationID != \"\" || v.Revision != nil || v.LeaseGeneration != nil || v.CurrentAppliedRevision != nil) { violations = append(violations, FieldViolation{Field: \"acquisition\", Code: \"invalid_tagged_value\"}) }")
+        lines.append("\tif v.Acquisition == \"prompt\" && (v.OperationID == \"\" || v.Revision == nil || v.LeaseGeneration != nil || v.CurrentAppliedRevision != nil) { violations = append(violations, FieldViolation{Field: \"acquisition\", Code: \"invalid_tagged_value\"}) }")
+        lines.append("\tif v.Acquisition == \"observation\" && (v.OperationID == \"\" || v.Revision == nil || v.LeaseGeneration == nil || v.CurrentAppliedRevision == nil) { violations = append(violations, FieldViolation{Field: \"acquisition\", Code: \"invalid_tagged_value\"}) }")
+    if name == "GatewayStopWorkRequest":
+        lines.append("\tif v.Acquisition == \"poll\" && v.OperationID != \"\" || v.Acquisition == \"prompt\" && v.OperationID == \"\" { violations = append(violations, FieldViolation{Field: \"acquisition\", Code: \"invalid_tagged_value\"}) }")
+    if name == "GatewayQualityAck":
+        lines.append("\tif v.Outcome == \"applied\" && (v.CurrentAppliedRevision == nil || *v.CurrentAppliedRevision != v.Revision) { violations = append(violations, FieldViolation{Field: \"current_applied_revision\", Code: \"invalid_tagged_value\"}) }")
+        lines.append("\tif v.Outcome == \"proven_prior\" && (v.CurrentAppliedRevision == nil || *v.CurrentAppliedRevision >= v.Revision) { violations = append(violations, FieldViolation{Field: \"current_applied_revision\", Code: \"invalid_tagged_value\"}) }")
+        lines.append("\tif v.Outcome == \"unknown\" && v.CurrentAppliedRevision != nil { violations = append(violations, FieldViolation{Field: \"current_applied_revision\", Code: \"invalid_tagged_value\"}) }")
    if name == "GatewayRegistration":
        lines.append("\tif v.ProtocolMinVersion > v.ProtocolMaxVersion { violations = append(violations, FieldViolation{Field: \"protocol_version\", Code: \"invalid_order\"}) }")
    if name == "ChannelFrame":
@@ -214,6 +234,30 @@ def generate_go(defs: dict[str, dict[str, Any]], schema_hash: str, version: str,
        "",
        "func (e ValidationError) Error() string { return \"protocol validation failed\" }",
        "",
+        "func validCanonicalUUID(value string) bool {",
+        "\tif len(value) != 36 || value[8] != '-' || value[13] != '-' || value[18] != '-' || value[23] != '-' { return false }",
+        "\tfor index, char := range []byte(value) { if index == 8 || index == 13 || index == 18 || index == 23 { continue }; if !((char >= '0' && char <= '9') || (char >= 'a' && char <= 'f')) { return false } }",
+        "\treturn value != \"00000000-0000-0000-0000-000000000000\"",
+        "}",
+        "",
+        "func rejectDuplicateJSONKeys(data []byte) error {",
+        "\tdecoder := json.NewDecoder(bytes.NewReader(data))",
+        "\tvar scan func(json.Token) error",
+        "\tscan = func(token json.Token) error {",
+        "\t\tdelim, ok := token.(json.Delim); if !ok { return nil }",
+        "\t\tswitch delim {",
+        "\t\tcase '{':",
+        "\t\t\tseen := map[string]struct{}{}",
+        "\t\t\tfor decoder.More() { keyToken, err := decoder.Token(); if err != nil { return err }; key, ok := keyToken.(string); if !ok { return errors.New(\"invalid JSON object key\") }; if _, exists := seen[key]; exists { return errors.New(\"duplicate JSON object key\") }; seen[key] = struct{}{}; value, err := decoder.Token(); if err != nil { return err }; if err := scan(value); err != nil { return err } }",
+        "\t\t\t_, err := decoder.Token(); return err",
+        "\t\tcase '[':",
+        "\t\t\tfor decoder.More() { value, err := decoder.Token(); if err != nil { return err }; if err := scan(value); err != nil { return err } }; _, err := decoder.Token(); return err",
+        "\t\t}",
+        "\t\treturn nil",
+        "\t}",
+        "\ttoken, err := decoder.Token(); if err != nil { return err }; return scan(token)",
+        "}",
+        "",
    ]
    for name in sorted(defs):
        if name == "FieldViolation":
@@ -224,7 +268,9 @@ def generate_go(defs: dict[str, dict[str, Any]], schema_hash: str, version: str,
        for prop_name, prop in definition.get("properties", {}).items():
            tag = prop_name + (",omitempty" if prop_name not in required else "")
            typ = prop_type(prop, "go")
-            if prop_name not in required and ref_name(prop):
+            if prop.get("x-optional-pointer"):
+                typ = "*" + typ
+            elif prop_name not in required and ref_name(prop):
                typ = "*" + typ
            out.append(f"\t{go_field(prop_name)} {typ} `json:\"{tag}\"`")
        out.extend(["}", ""])
@@ -239,6 +285,7 @@ def generate_go(defs: dict[str, dict[str, Any]], schema_hash: str, version: str,
        out.append(f"func Decode{name}(data []byte) ({name}, error) {{")
        out.append(f"\tvar value {name}")
        out.append("\tif len(data) > 1024*1024 { return value, errors.New(\"protocol payload exceeds limit\") }")
+        out.append("\tif err := rejectDuplicateJSONKeys(data); err != nil { return value, err }")
        out.append("\tvar fields map[string]json.RawMessage")
        out.append("\tif err := json.Unmarshal(data, &fields); err != nil { return value, err }")
        required_fields = sorted(defs[name].get("required", []))
@@ -295,23 +342,29 @@ def generate_go(defs: dict[str, dict[str, Any]], schema_hash: str, version: str,
        "\tif len(profiles) == 0 { return CapabilityProfile{}, ErrNoCapabilityOverlap }",
        "\tselected := profiles[0]",
        "\tif err := selected.Validate(); err != nil { return CapabilityProfile{}, ErrNoCapabilityOverlap }",
-        "\tcommon := append([]string(nil), selected.ClientDecode...)",
+        "\tcommonVideo := append([]VideoProfile(nil), selected.VideoProfiles...)",
+        "\tcommonAudio := append([]AudioProfile(nil), selected.AudioProfiles...)",
        "\tfor _, profile := range profiles[1:] {",
-        "\t\tif err := profile.Validate(); err != nil || profile.Transport != selected.Transport || profile.Framing != selected.Framing || profile.Media != selected.Media || profile.Audio != selected.Audio || profile.SourceRateControl != selected.SourceRateControl { return CapabilityProfile{}, ErrNoCapabilityOverlap }",
-        "\t\tnext := common[:0]",
-        "\t\tfor _, candidate := range common { for _, offered := range profile.ClientDecode { if candidate == offered { next = append(next, candidate); break } } }",
-        "\t\tcommon = next",
-        "\t\tif len(common) == 0 { return CapabilityProfile{}, ErrNoCapabilityOverlap }",
+        "\t\tif err := profile.Validate(); err != nil || profile.Transport != selected.Transport || profile.Framing != selected.Framing || profile.Media != selected.Media || profile.SourceRateControl != selected.SourceRateControl { return CapabilityProfile{}, ErrNoCapabilityOverlap }",
+        "\t\tnextVideo := commonVideo[:0]",
+        "\t\tfor _, candidate := range commonVideo { for _, offered := range profile.VideoProfiles { if candidate == offered { nextVideo = append(nextVideo, candidate); break } } }",
+        "\t\tcommonVideo = nextVideo",
+        "\t\tnextAudio := commonAudio[:0]",
+        "\t\tfor _, candidate := range commonAudio { for _, offered := range profile.AudioProfiles { if candidate == offered { nextAudio = append(nextAudio, candidate); break } } }",
+        "\t\tcommonAudio = nextAudio",
+        "\t\tif len(commonVideo) == 0 || len(commonAudio) == 0 { return CapabilityProfile{}, ErrNoCapabilityOverlap }",
        "\t}",
-        "\tselected.ClientDecode = common",
+        "\tselected.VideoProfiles = commonVideo",
+        "\tselected.AudioProfiles = commonAudio",
        "\treturn selected, nil",
        "}",
        "",
    ])
    out.extend([
        "func (v TunnelAdmissionRequest) DeviceAdmissionTranscript() []byte {",
-        "\tfields := []string{v.SessionID, v.GatewayID, v.Audience, v.Grant, fmt.Sprintf(\"%d\", v.ReconnectSequence), v.ClientNonce, v.Capabilities.Transport, v.Capabilities.Framing, v.Capabilities.Media, v.Capabilities.Audio, v.Capabilities.SourceRateControl, fmt.Sprintf(\"%d\", len(v.Capabilities.ClientDecode))}",
-        "\tfields = append(fields, v.Capabilities.ClientDecode...)",
+        "\tfields := []string{v.SessionID, v.GatewayID, v.Audience, v.Grant, fmt.Sprintf(\"%d\", v.ReconnectSequence), v.ClientNonce, v.Capabilities.Transport, v.Capabilities.Framing, v.Capabilities.Media, v.Capabilities.SourceRateControl, fmt.Sprintf(\"%d\", len(v.Capabilities.VideoProfiles)), fmt.Sprintf(\"%d\", len(v.Capabilities.AudioProfiles))}",
+        "\tfor _, profile := range v.Capabilities.VideoProfiles { fields = append(fields, profile.Codec, fmt.Sprintf(\"%d\", profile.BitDepth), profile.ChromaSubsampling, profile.ColorSpace, profile.TransferFunction) }",
+        "\tfor _, profile := range v.Capabilities.AudioProfiles { fields = append(fields, profile.Codec, fmt.Sprintf(\"%d\", profile.SampleRateHz), fmt.Sprintf(\"%d\", profile.Channels), profile.ChannelLayout, fmt.Sprintf(\"%d\", profile.PacketDurationMs)) }",
        "\tvar transcript strings.Builder",
        "\ttranscript.WriteString(\"versevdi/tunnel-admission/v1\")",
        "\tfor _, field := range fields { fmt.Fprintf(&transcript, \"%d:%s\", len(field), field) }",
@@ -386,11 +439,14 @@ def rust_validation(definition: dict[str, Any]) -> list[str]:
                lines.append(f"        {prefix}if !valid_rfc3339_utc({value}.as_str()) {{ return Err(ValidationError::new(\"{prop_name}\", \"invalid_time\")); }}")
            if prop.get("format") == "base64url":
                lines.append(f"        {prefix}if !valid_base64_url({value}.as_str()) {{ return Err(ValidationError::new(\"{prop_name}\", \"invalid_format\")); }}")
+            if prop.get("format") == "uuid":
+                lines.append(f"        {prefix}if !valid_canonical_uuid({value}.as_str()) {{ return Err(ValidationError::new(\"{prop_name}\", \"invalid_uuid\")); }}")
        if prop.get("type") == "integer":
+            numeric = f"*{value}" if prop_name not in required else value
            if "minimum" in prop:
-                lines.append(f"        {prefix}if {value} < {prop['minimum']} {{ return Err(ValidationError::new(\"{prop_name}\", \"minimum\")); }}")
+                lines.append(f"        {prefix}if {numeric} < {prop['minimum']} {{ return Err(ValidationError::new(\"{prop_name}\", \"minimum\")); }}")
            if "maximum" in prop:
-                lines.append(f"        {prefix}if {value} > {prop['maximum']} {{ return Err(ValidationError::new(\"{prop_name}\", \"maximum\")); }}")
+                lines.append(f"        {prefix}if {numeric} > {prop['maximum']} {{ return Err(ValidationError::new(\"{prop_name}\", \"maximum\")); }}")
        if prop.get("type") == "array":
            if "minItems" in prop:
                lines.append(f"        {prefix}if {value}.len() < {prop['minItems']} {{ return Err(ValidationError::new(\"{prop_name}\", \"min_items\")); }}")
@@ -406,7 +462,7 @@ def rust_validation(definition: dict[str, Any]) -> list[str]:
            if "enum" in items:
                allowed = " && ".join(f'item != \"{item}\"' for item in items["enum"])
                lines.append(f"        {prefix}for item in {value}.iter() {{ if {allowed} {{ return Err(ValidationError::new(\"{prop_name}\", \"invalid_item\")); }} }}")
-            if prop.get("uniqueItems") and items.get("type") == "string":
+            if prop.get("uniqueItems"):
                lines.append(f"        {prefix}for (index, item) in {value}.iter().enumerate() {{ if {value}[..index].contains(item) {{ return Err(ValidationError::new(\"{prop_name}\", \"duplicate_item\")); }} }}")
            item_ref = ref_name(items)
            if item_ref:
@@ -419,6 +475,22 @@ def rust_validation(definition: dict[str, Any]) -> list[str]:
    name = definition["name"]
    if name in {"AllocationPolicy", "ManifestBounds"}:
        lines.append("        if self.minimumKbps > self.targetKbps || self.targetKbps > self.maximumKbps { return Err(ValidationError::new(\"bounds\", \"invalid_order\")); }")
+    if name == "SessionQualityLimits":
+        lines.append("        if self.bitrateMinimumKbps > self.bitrateTargetKbps || self.bitrateTargetKbps > self.bitrateMaximumKbps { return Err(ValidationError::new(\"bitrate_bounds\", \"invalid_order\")); }")
+    if name in {"SelectedSessionDescriptor", "ProviderStreamPolicy"}:
+        lines.append("        if self.bitrateTargetKbps > self.bitrateMaximumKbps { return Err(ValidationError::new(\"bitrate_bounds\", \"invalid_order\")); }")
+    if name == "BitratePreference":
+        lines.append("        if self.mode == \"auto\" && self.targetKbps.is_some() || self.mode == \"explicit\" && self.targetKbps.is_none() { return Err(ValidationError::new(\"target_kbps\", \"invalid_tagged_value\")); }")
+    if name == "GatewayQualityWorkRequest":
+        lines.append("        if self.acquisition == \"poll\" && (self.operationId.is_some() || self.revision.is_some() || self.leaseGeneration.is_some() || self.currentAppliedRevision.is_some()) { return Err(ValidationError::new(\"acquisition\", \"invalid_tagged_value\")); }")
+        lines.append("        if self.acquisition == \"prompt\" && (self.operationId.is_none() || self.revision.is_none() || self.leaseGeneration.is_some() || self.currentAppliedRevision.is_some()) { return Err(ValidationError::new(\"acquisition\", \"invalid_tagged_value\")); }")
+        lines.append("        if self.acquisition == \"observation\" && (self.operationId.is_none() || self.revision.is_none() || self.leaseGeneration.is_none() || self.currentAppliedRevision.is_none()) { return Err(ValidationError::new(\"acquisition\", \"invalid_tagged_value\")); }")
+    if name == "GatewayStopWorkRequest":
+        lines.append("        if self.acquisition == \"poll\" && self.operationId.is_some() || self.acquisition == \"prompt\" && self.operationId.is_none() { return Err(ValidationError::new(\"acquisition\", \"invalid_tagged_value\")); }")
+    if name == "GatewayQualityAck":
+        lines.append("        if self.outcome == \"applied\" && self.currentAppliedRevision != Some(self.revision) { return Err(ValidationError::new(\"current_applied_revision\", \"invalid_tagged_value\")); }")
+        lines.append("        if self.outcome == \"proven_prior\" && self.currentAppliedRevision.map_or(true, |current| current >= self.revision) { return Err(ValidationError::new(\"current_applied_revision\", \"invalid_tagged_value\")); }")
+        lines.append("        if self.outcome == \"unknown\" && self.currentAppliedRevision.is_some() { return Err(ValidationError::new(\"current_applied_revision\", \"invalid_tagged_value\")); }")
    if name == "GatewayRegistration":
        lines.append("        if self.protocolMinVersion > self.protocolMaxVersion { return Err(ValidationError::new(\"protocol_version\", \"invalid_order\")); }")
    if name == "ChannelFrame":
@@ -473,6 +545,10 @@ def generate_rust(defs: dict[str, dict[str, Any]], schema_hash: str, compatibili
        "    let fraction = &bytes[20..bytes.len() - 1];",
        "    bytes[19] == b'.' && !fraction.is_empty() && fraction.len() <= 9 && fraction.iter().all(u8::is_ascii_digit) && *fraction.last().unwrap() != b'0'",
        "}",
+        "fn valid_canonical_uuid(value: &str) -> bool {",
+        "    let bytes = value.as_bytes();",
+        "    bytes.len() == 36 && [8, 13, 18, 23].iter().all(|index| bytes[*index] == b'-') && bytes.iter().enumerate().all(|(index, byte)| [8, 13, 18, 23].contains(&index) || byte.is_ascii_digit() || (b'a'..=b'f').contains(byte)) && value != \"00000000-0000-0000-0000-000000000000\"",
+        "}",
        "",
    ]
    for name in sorted(defs):
@@ -515,9 +591,12 @@ def generate_rust(defs: dict[str, dict[str, Any]], schema_hash: str, compatibili
            out.extend([
                "    pub fn device_admission_transcript(&self) -> Vec<u8> {",
                "        let reconnect_sequence = self.reconnectSequence.to_string();",
-                "        let client_decode_count = self.capabilities.clientDecode.len().to_string();",
-                "        let mut fields = vec![self.sessionId.as_str(), self.gatewayId.as_str(), self.audience.as_str(), self.grant.as_str(), reconnect_sequence.as_str(), self.clientNonce.as_str(), self.capabilities.transport.as_str(), self.capabilities.framing.as_str(), self.capabilities.media.as_str(), self.capabilities.audio.as_str(), self.capabilities.sourceRateControl.as_str(), client_decode_count.as_str()];",
-                "        fields.extend(self.capabilities.clientDecode.iter().map(String::as_str));",
+                "        let video_count = self.capabilities.videoProfiles.len().to_string();",
+                "        let audio_count = self.capabilities.audioProfiles.len().to_string();",
+                "        let mut owned = vec![self.sessionId.clone(), self.gatewayId.clone(), self.audience.clone(), self.grant.clone(), reconnect_sequence, self.clientNonce.clone(), self.capabilities.transport.clone(), self.capabilities.framing.clone(), self.capabilities.media.clone(), self.capabilities.sourceRateControl.clone(), video_count, audio_count];",
+                "        for profile in &self.capabilities.videoProfiles { owned.extend([profile.codec.clone(), profile.bitDepth.to_string(), profile.chromaSubsampling.clone(), profile.colorSpace.clone(), profile.transferFunction.clone()]); }",
+                "        for profile in &self.capabilities.audioProfiles { owned.extend([profile.codec.clone(), profile.sampleRateHz.to_string(), profile.channels.to_string(), profile.channelLayout.clone(), profile.packetDurationMs.to_string()]); }",
+                "        let fields: Vec<&str> = owned.iter().map(String::as_str).collect();",
                "        let mut transcript = String::from(\"versevdi/tunnel-admission/v1\");",
                "        for field in fields { transcript.push_str(&format!(\"{}:{}\", field.as_bytes().len(), field)); }",
                "        transcript.into_bytes()",
@@ -545,9 +624,10 @@ def generate_rust(defs: dict[str, dict[str, Any]], schema_hash: str, compatibili
        "    selected.validate().map_err(|_| ValidationError::new(\"capabilities\", \"no_overlap\"))?;",
        "    for profile in &profiles[1..] {",
        "        profile.validate().map_err(|_| ValidationError::new(\"capabilities\", \"no_overlap\"))?;",
-        "        if profile.transport != selected.transport || profile.framing != selected.framing || profile.media != selected.media || profile.audio != selected.audio || profile.sourceRateControl != selected.sourceRateControl { return Err(ValidationError::new(\"capabilities\", \"no_overlap\")); }",
-        "        selected.clientDecode.retain(|candidate| profile.clientDecode.contains(candidate));",
-        "        if selected.clientDecode.is_empty() { return Err(ValidationError::new(\"capabilities\", \"no_overlap\")); }",
+        "        if profile.transport != selected.transport || profile.framing != selected.framing || profile.media != selected.media || profile.sourceRateControl != selected.sourceRateControl { return Err(ValidationError::new(\"capabilities\", \"no_overlap\")); }",
+        "        selected.videoProfiles.retain(|candidate| profile.videoProfiles.contains(candidate));",
+        "        selected.audioProfiles.retain(|candidate| profile.audioProfiles.contains(candidate));",
+        "        if selected.videoProfiles.is_empty() || selected.audioProfiles.is_empty() { return Err(ValidationError::new(\"capabilities\", \"no_overlap\")); }",
        "    }",
        "    Ok(selected)",
        "}",
@@ -586,6 +666,8 @@ def swift_validation(definition: dict[str, Any]) -> list[str]:
                lines.append(f"        {prefix}if !validRFC3339UTC({value}) {{ throw ContractValidationError(field: \"{prop_name}\", code: \"invalid_time\") }}")
            if prop.get("format") == "base64url":
                lines.append(f"        {prefix}if !validBase64URL({value}) {{ throw ContractValidationError(field: \"{prop_name}\", code: \"invalid_format\") }}")
+            if prop.get("format") == "uuid":
+                lines.append(f"        {prefix}if !validCanonicalUUID({value}) {{ throw ContractValidationError(field: \"{prop_name}\", code: \"invalid_uuid\") }}")
        if prop.get("type") == "integer":
            if "minimum" in prop:
                lines.append(f"        {prefix}if {value} < {prop['minimum']} {{ throw ContractValidationError(field: \"{prop_name}\", code: \"minimum\") }}")
@@ -606,8 +688,8 @@ def swift_validation(definition: dict[str, Any]) -> list[str]:
            if "enum" in items:
                allowed = ", ".join(f'\"{item}\"' for item in items["enum"])
                lines.append(f"        {prefix}for item in {value} where ![{allowed}].contains(item) {{ throw ContractValidationError(field: \"{prop_name}\", code: \"invalid_item\") }}")
-            if prop.get("uniqueItems") and items.get("type") == "string":
-                lines.append(f"        {prefix}if Set({value}).count != {value}.count {{ throw ContractValidationError(field: \"{prop_name}\", code: \"duplicate_item\") }}")
+            if prop.get("uniqueItems"):
+                lines.append(f"        {prefix}for (index, item) in {value}.enumerated() where {value}[..<index].contains(item) {{ throw ContractValidationError(field: \"{prop_name}\", code: \"duplicate_item\") }}")
            item_ref = ref_name(items)
            if item_ref:
                lines.append(f"        {prefix}for item in {value} {{ try item.validate() }}")
@@ -619,6 +701,22 @@ def swift_validation(definition: dict[str, Any]) -> list[str]:
    name = definition["name"]
    if name in {"AllocationPolicy", "ManifestBounds"}:
        lines.append("        if minimumKbps > targetKbps || targetKbps > maximumKbps { throw ContractValidationError(field: \"bounds\", code: \"invalid_order\") }")
+    if name == "SessionQualityLimits":
+        lines.append("        if bitrateMinimumKbps > bitrateTargetKbps || bitrateTargetKbps > bitrateMaximumKbps { throw ContractValidationError(field: \"bitrate_bounds\", code: \"invalid_order\") }")
+    if name in {"SelectedSessionDescriptor", "ProviderStreamPolicy"}:
+        lines.append("        if bitrateTargetKbps > bitrateMaximumKbps { throw ContractValidationError(field: \"bitrate_bounds\", code: \"invalid_order\") }")
+    if name == "BitratePreference":
+        lines.append("        if mode == \"auto\" && targetKbps != nil || mode == \"explicit\" && targetKbps == nil { throw ContractValidationError(field: \"target_kbps\", code: \"invalid_tagged_value\") }")
+    if name == "GatewayQualityWorkRequest":
+        lines.append("        if acquisition == \"poll\" && (operationId != nil || revision != nil || leaseGeneration != nil || currentAppliedRevision != nil) { throw ContractValidationError(field: \"acquisition\", code: \"invalid_tagged_value\") }")
+        lines.append("        if acquisition == \"prompt\" && (operationId == nil || revision == nil || leaseGeneration != nil || currentAppliedRevision != nil) { throw ContractValidationError(field: \"acquisition\", code: \"invalid_tagged_value\") }")
+        lines.append("        if acquisition == \"observation\" && (operationId == nil || revision == nil || leaseGeneration == nil || currentAppliedRevision == nil) { throw ContractValidationError(field: \"acquisition\", code: \"invalid_tagged_value\") }")
+    if name == "GatewayStopWorkRequest":
+        lines.append("        if acquisition == \"poll\" && operationId != nil || acquisition == \"prompt\" && operationId == nil { throw ContractValidationError(field: \"acquisition\", code: \"invalid_tagged_value\") }")
+    if name == "GatewayQualityAck":
+        lines.append("        if outcome == \"applied\" && currentAppliedRevision != revision { throw ContractValidationError(field: \"current_applied_revision\", code: \"invalid_tagged_value\") }")
+        lines.append("        if outcome == \"proven_prior\" && (currentAppliedRevision == nil || currentAppliedRevision! >= revision) { throw ContractValidationError(field: \"current_applied_revision\", code: \"invalid_tagged_value\") }")
+        lines.append("        if outcome == \"unknown\" && currentAppliedRevision != nil { throw ContractValidationError(field: \"current_applied_revision\", code: \"invalid_tagged_value\") }")
    if name == "GatewayRegistration":
        lines.append("        if protocolMinVersion > protocolMaxVersion { throw ContractValidationError(field: \"protocol_version\", code: \"invalid_order\") }")
    if name == "ChannelFrame":
@@ -637,6 +735,67 @@ def generate_swift(defs: dict[str, dict[str, Any]], schema_hash: str, compatibil
        f'public let nMinus2WireVersion = "{compatibility["n_minus_2"]}"',
        "public struct ContractValidationError: Error, Equatable { public let field: String; public let code: String }",
        "private struct AnyCodingKey: CodingKey { let stringValue: String; let intValue: Int?; init?(stringValue: String) { self.stringValue = stringValue; self.intValue = nil }; init?(intValue: Int) { self.stringValue = String(intValue); self.intValue = intValue } }",
+        "private func rejectDuplicateJSONKeys(_ data: Data) throws {",
+        "    guard data.count <= 1_048_576 else { throw ContractValidationError(field: \"json\", code: \"payload_too_large\") }",
+        "    var index = 0",
+        "    func skipWhitespace() { while index < data.count && [9, 10, 13, 32].contains(data[index]) { index += 1 } }",
+        "    func parseString() throws -> String {",
+        "        guard index < data.count, data[index] == 34 else { throw ContractValidationError(field: \"json\", code: \"invalid_json\") }",
+        "        let start = index",
+        "        index += 1",
+        "        while index < data.count {",
+        "            if data[index] == 92 { index += 2; continue }",
+        "            if data[index] == 34 { index += 1; return try JSONDecoder().decode(String.self, from: data[start..<index]) }",
+        "            index += 1",
+        "        }",
+        "        throw ContractValidationError(field: \"json\", code: \"invalid_json\")",
+        "    }",
+        "    func parseValue(_ depth: Int) throws {",
+        "        guard depth <= 64 else { throw ContractValidationError(field: \"json\", code: \"nesting_too_deep\") }",
+        "        skipWhitespace()",
+        "        guard index < data.count else { throw ContractValidationError(field: \"json\", code: \"invalid_json\") }",
+        "        if data[index] == 123 {",
+        "            index += 1",
+        "            var keys = Set<String>()",
+        "            skipWhitespace()",
+        "            if index < data.count, data[index] == 125 { index += 1; return }",
+        "            while true {",
+        "                skipWhitespace()",
+        "                let key = try parseString()",
+        "                guard keys.insert(key).inserted else { throw ContractValidationError(field: key, code: \"duplicate_field\") }",
+        "                skipWhitespace()",
+        "                guard index < data.count, data[index] == 58 else { throw ContractValidationError(field: \"json\", code: \"invalid_json\") }",
+        "                index += 1",
+        "                try parseValue(depth + 1)",
+        "                skipWhitespace()",
+        "                guard index < data.count else { throw ContractValidationError(field: \"json\", code: \"invalid_json\") }",
+        "                if data[index] == 125 { index += 1; return }",
+        "                guard data[index] == 44 else { throw ContractValidationError(field: \"json\", code: \"invalid_json\") }",
+        "                index += 1",
+        "            }",
+        "        }",
+        "        if data[index] == 91 {",
+        "            index += 1",
+        "            skipWhitespace()",
+        "            if index < data.count, data[index] == 93 { index += 1; return }",
+        "            while true {",
+        "                try parseValue(depth + 1)",
+        "                skipWhitespace()",
+        "                guard index < data.count else { throw ContractValidationError(field: \"json\", code: \"invalid_json\") }",
+        "                if data[index] == 93 { index += 1; return }",
+        "                guard data[index] == 44 else { throw ContractValidationError(field: \"json\", code: \"invalid_json\") }",
+        "                index += 1",
+        "            }",
+        "        }",
+        "        if data[index] == 34 { _ = try parseString(); return }",
+        "        let start = index",
+        "        while index < data.count && ![9, 10, 13, 32, 44, 93, 125].contains(data[index]) { index += 1 }",
+        "        guard index > start else { throw ContractValidationError(field: \"json\", code: \"invalid_json\") }",
+        "    }",
+        "    try parseValue(0)",
+        "    skipWhitespace()",
+        "    guard index == data.count else { throw ContractValidationError(field: \"json\", code: \"trailing_json\") }",
+        "}",
        "private func validBase64URL(_ value: String) -> Bool {",
        "    guard !value.isEmpty, value.utf8.allSatisfy({ byte in",
        "        (byte >= 65 && byte <= 90) || (byte >= 97 && byte <= 122) || (byte >= 48 && byte <= 57) || byte == 45 || byte == 95",
@@ -663,6 +822,11 @@ def generate_swift(defs: dict[str, dict[str, Any]], schema_hash: str, compatibil
        "    let fraction = bytes[20..<(bytes.count - 1)]",
        "    return bytes[19] == 46 && !fraction.isEmpty && fraction.count <= 9 && fraction.allSatisfy { $0 >= 48 && $0 <= 57 } && fraction.last != 48",
        "}",
+        "private func validCanonicalUUID(_ value: String) -> Bool {",
+        "    let bytes = Array(value.utf8)",
+        "    guard bytes.count == 36, bytes[8] == 45, bytes[13] == 45, bytes[18] == 45, bytes[23] == 45, value != \"00000000-0000-0000-0000-000000000000\" else { return false }",
+        "    return bytes.enumerated().allSatisfy { index, byte in [8, 13, 18, 23].contains(index) || (byte >= 48 && byte <= 57) || (byte >= 97 && byte <= 102) }",
+        "}",
        "",
    ]
    for name in sorted(defs):
@@ -704,7 +868,7 @@ def generate_swift(defs: dict[str, dict[str, Any]], schema_hash: str, compatibil
        out.append(f"        try self.init({', '.join(decoded)})")
        out.extend(["    }", "", "    public func validate() throws {"])
        out.extend(swift_validation(definition))
-        out.extend(["    }", "", "    public static func decodeJSON(_ data: Data) throws -> Self { try JSONDecoder().decode(Self.self, from: data) }", "    public func encodeJSON() throws -> Data { try validate(); return try JSONEncoder().encode(self) }", "}", ""])
+        out.extend(["    }", "", "    public static func decodeJSON(_ data: Data) throws -> Self { try rejectDuplicateJSONKeys(data); return try JSONDecoder().decode(Self.self, from: data) }", "    public func encodeJSON() throws -> Data { try validate(); return try JSONEncoder().encode(self) }", "}", ""])
    out.extend([
        "public func deviceRegistrationProofTranscript(serverID: Data, principalID: Data, deviceID: Data, challenge: Data, expiryUnixMilliseconds: Int64) throws -> Data {",
        "    for (field, value, length) in [(\"server_id\", serverID, 16), (\"principal_id\", principalID, 16), (\"device_id\", deviceID, 16), (\"challenge\", challenge, 32)] {",
@@ -723,8 +887,9 @@ def generate_swift(defs: dict[str, dict[str, Any]], schema_hash: str, compatibil
        "",
        "public extension TunnelAdmissionRequest {",
        "    func deviceAdmissionTranscript() -> Data {",
-        "        var fields = [sessionId, gatewayId, audience, grant, String(reconnectSequence), clientNonce, capabilities.transport, capabilities.framing, capabilities.media, capabilities.audio, capabilities.sourceRateControl, String(capabilities.clientDecode.count)]",
-        "        fields.append(contentsOf: capabilities.clientDecode)",
+        "        var fields = [sessionId, gatewayId, audience, grant, String(reconnectSequence), clientNonce, capabilities.transport, capabilities.framing, capabilities.media, capabilities.sourceRateControl, String(capabilities.videoProfiles.count), String(capabilities.audioProfiles.count)]",
+        "        for profile in capabilities.videoProfiles { fields.append(contentsOf: [profile.codec, String(profile.bitDepth), profile.chromaSubsampling, profile.colorSpace, profile.transferFunction]) }",
+        "        for profile in capabilities.audioProfiles { fields.append(contentsOf: [profile.codec, String(profile.sampleRateHz), String(profile.channels), profile.channelLayout, String(profile.packetDurationMs)]) }",
        "        var transcript = \"versevdi/tunnel-admission/v1\"",
        "        for field in fields { transcript += \"\\(field.utf8.count):\\(field)\" }",
        "        return Data(transcript.utf8)",
@@ -735,14 +900,16 @@ def generate_swift(defs: dict[str, dict[str, Any]], schema_hash: str, compatibil
        "    static func intersection(_ profiles: [CapabilityProfile]) throws -> CapabilityProfile {",
        "        guard let selected = profiles.first else { throw ContractValidationError(field: \"capabilities\", code: \"no_overlap\") }",
        "        try selected.validate()",
-        "        var common = selected.clientDecode",
+        "        var commonVideo = selected.videoProfiles",
+        "        var commonAudio = selected.audioProfiles",
        "        for profile in profiles.dropFirst() {",
        "            try profile.validate()",
-        "            if profile.transport != selected.transport || profile.framing != selected.framing || profile.media != selected.media || profile.audio != selected.audio || profile.sourceRateControl != selected.sourceRateControl { throw ContractValidationError(field: \"capabilities\", code: \"no_overlap\") }",
-        "            common = common.filter { profile.clientDecode.contains($0) }",
-        "            if common.isEmpty { throw ContractValidationError(field: \"capabilities\", code: \"no_overlap\") }",
+        "            if profile.transport != selected.transport || profile.framing != selected.framing || profile.media != selected.media || profile.sourceRateControl != selected.sourceRateControl { throw ContractValidationError(field: \"capabilities\", code: \"no_overlap\") }",
+        "            commonVideo = commonVideo.filter { profile.videoProfiles.contains($0) }",
+        "            commonAudio = commonAudio.filter { profile.audioProfiles.contains($0) }",
+        "            if commonVideo.isEmpty || commonAudio.isEmpty { throw ContractValidationError(field: \"capabilities\", code: \"no_overlap\") }",
        "        }",
-        "        return try CapabilityProfile(transport: selected.transport, framing: selected.framing, media: selected.media, audio: selected.audio, sourceRateControl: selected.sourceRateControl, clientDecode: common)",
+        "        return try CapabilityProfile(transport: selected.transport, framing: selected.framing, media: selected.media, sourceRateControl: selected.sourceRateControl, videoProfiles: commonVideo, audioProfiles: commonAudio)",
        "    }",
        "}",
        "",
@@ -2,6 +2,7 @@ package main

 import (
 	"crypto/sha256"
+	"encoding/binary"
 	"encoding/hex"
 	"encoding/json"
 	"fmt"
@@ -101,6 +102,15 @@ func evaluate(version, kind, input string) string {
 			Profile:       protocol.ManifestProfile{ID: "standard", Bounds: protocol.ManifestBounds{MinimumKbps: 1, TargetKbps: 2, MaximumKbps: 3}},
 			Grant:         protocol.GrantReference{OpaqueValue: parts["grant"], ExpiresAt: parts["expires_at"], Audience: parts["audience"]},
 			CorrelationID: "correlation-1",
+			SelectedDescriptor: protocol.SelectedSessionDescriptor{
+				VideoProfile:        protocol.VideoProfile{Codec: "h264", BitDepth: 8, ChromaSubsampling: "4:2:0", ColorSpace: "bt709-limited", TransferFunction: "sdr"},
+				AudioProfile:        protocol.AudioProfile{Codec: "opus", SampleRateHz: 48000, Channels: 2, ChannelLayout: "stereo", PacketDurationMs: 5},
+				DisplayMode:         protocol.DisplayMode{ResolutionWidth: 1920, ResolutionHeight: 1080, Fps: 60},
+				BitrateTargetKbps:   12000,
+				BitrateMaximumKbps:  20000,
+				Adjustment:          protocol.SessionAdjustment{DisplayReason: "none", BitrateReason: "none"},
+				MediaTimestampBasis: "gateway-send-wall-clock-ms",
+			},
 		}
 		if value.Validate() == nil {
 			return "valid"
@@ -123,6 +133,8 @@ func evaluate(version, kind, input string) string {
 		value := protocol.SessionRequest{
 			ClientDeviceID: parts["client_device_id"], DeviceKeyID: parts["device_key_id"],
 			PoolID: parts["pool_id"], IdempotencyKey: parts["idempotency_key"],
+			VideoProfiles:     []protocol.VideoProfile{{Codec: "h264", BitDepth: 8, ChromaSubsampling: "4:2:0", ColorSpace: "bt709-limited", TransferFunction: "sdr"}},
+			BitratePreference: protocol.BitratePreference{Mode: "auto"},
 		}
 		if value.Validate() == nil {
 			return "valid"
@@ -309,6 +321,13 @@ func classifyGatewayInput(encoded string) string {
 		if len(body) != 4 {
 			return "invalid:length"
 		}
+	case 8:
+		if len(body) != 8 {
+			return "invalid:length"
+		}
+		if body[0] > 15 || body[3] > 3 {
+			return "invalid:field"
+		}
 	default:
 		return "invalid:kind"
 	}
@@ -352,6 +371,22 @@ func classifyGatewayFeedback(encoded string) string {
 			if len(body) == 0 {
 				return "valid"
 			}
+		case 4:
+			if len(body) != 24 {
+				return "invalid:length"
+			}
+			if binary.BigEndian.Uint64(body[16:]) == 0 || allZero(body[:16]) {
+				return "invalid:field"
+			}
+			return "valid"
+		case 5:
+			if len(body) != 16 {
+				return "invalid:length"
+			}
+			if allZero(body) {
+				return "invalid:field"
+			}
+			return "valid"
 		default:
 			return "invalid:type"
 		}
@@ -386,6 +421,15 @@ func classifyGatewayFeedback(encoded string) string {
 	return "invalid:field"
 }

+func allZero(value []byte) bool {
+	for _, item := range value {
+		if item != 0 {
+			return false
+		}
+	}
+	return true
+}
+
 func validFECStatus(body []byte) bool {
 	if len(body) != 21 || int(body[10])<<8|int(body[11]) == 0 || int(body[14])<<8|int(body[15]) > int(body[10])<<8|int(body[11]) || int(body[16])<<8|int(body[17]) > int(body[12])<<8|int(body[13]) || body[18] > 100 || body[20] == 0 || body[19] >= body[20] {
 		return false
@@ -38,6 +38,8 @@ fn evaluate(version: &str, kind: &str, input: &str) -> &'static str {
            values.get("device_key_id").cloned().unwrap_or_default(),
            values.get("pool_id").cloned().unwrap_or_default(),
            values.get("idempotency_key").cloned().unwrap_or_default(),
+            vec![VideoProfile::new("h264".into(), 8, "4:2:0".into(), "bt709-limited".into(), "sdr".into()).unwrap()],
+            BitratePreference::new("auto".into(), None).unwrap(),
            None,
        ) {
            Ok(_) => "valid",
@@ -184,6 +186,9 @@ fn classify_gateway_input(encoded: &str) -> &'static str {
        }
        7 if body.len() == 4 => "valid",
        7 => "invalid:length",
+        8 if body.len() != 8 => "invalid:length",
+        8 if body[0] > 15 || body[3] > 3 => "invalid:field",
+        8 => "valid",
        _ => "invalid:kind",
    }
 }
@@ -219,6 +224,12 @@ fn classify_gateway_feedback(encoded: &str) -> &'static str {
            2 => "invalid:field",
            3 if body.is_empty() => "valid",
            3 => "invalid:length",
+            4 if body.len() == 24 && body[..16].iter().any(|value| *value != 0) && body[16..24].iter().any(|value| *value != 0) => "valid",
+            4 if body.len() != 24 => "invalid:length",
+            4 => "invalid:field",
+            5 if body.len() == 16 && body.iter().any(|value| *value != 0) => "valid",
+            5 if body.len() != 16 => "invalid:length",
+            5 => "invalid:field",
            _ => "invalid:type",
        };
    }
@@ -26,6 +26,8 @@ func evaluate(_ version: String, _ kind: String, _ input: String) -> String {
        guard (try? SessionRequest(
            clientDeviceId: values["client_device_id"] ?? "", deviceKeyId: values["device_key_id"] ?? "",
            poolId: values["pool_id"] ?? "", idempotencyKey: values["idempotency_key"] ?? "",
+            videoProfiles: [try! VideoProfile(codec: "h264", bitDepth: 8, chromaSubsampling: "4:2:0", colorSpace: "bt709-limited", transferFunction: "sdr")],
+            bitratePreference: try! BitratePreference(mode: "auto", targetKbps: nil),
            requestedDisplayMode: nil
        )) != nil else { return "invalid:required" }
        return "valid"
@@ -136,6 +138,9 @@ func classifyGatewayInput(_ encoded: String) -> String {
        let height = Int(body[6]) * 256 + Int(body[7])
        return width > 0 && height > 0 && x < width && y < height ? "valid" : "invalid:field"
    case 7: return body.count == 4 ? "valid" : "invalid:length"
+    case 8:
+        guard body.count == 8 else { return "invalid:length" }
+        return body[0] <= 15 && body[3] <= 3 ? "valid" : "invalid:field"
    default: return "invalid:kind"
    }
 }
@@ -156,6 +161,12 @@ func classifyGatewayFeedback(_ encoded: String) -> String {
        case 2:
            return validFECStatus(body) ? "valid" : "invalid:field"
        case 3: return body.isEmpty ? "valid" : "invalid:length"
+        case 4:
+            guard body.count == 24 else { return "invalid:length" }
+            return body[0...15].contains(where: { $0 != 0 }) && body[16...23].contains(where: { $0 != 0 }) ? "valid" : "invalid:field"
+        case 5:
+            guard body.count == 16 else { return "invalid:length" }
+            return body.contains(where: { $0 != 0 }) ? "valid" : "invalid:field"
        default: return "invalid:type"
        }
    }
@@ -4,12 +4,17 @@ from __future__ import annotations
 import pathlib
 import subprocess
 import tempfile
+import os

 ROOT = pathlib.Path(__file__).resolve().parents[1]


 def run(command: list[str]) -> None:
-    result = subprocess.run(command, cwd=ROOT, text=True, capture_output=True)
+    environment = os.environ.copy()
+    cache_root = pathlib.Path(tempfile.gettempdir()) / "versevdi-protocol-module-cache"
+    environment.setdefault("CLANG_MODULE_CACHE_PATH", str(cache_root / "clang"))
+    environment.setdefault("SWIFT_MODULECACHE_PATH", str(cache_root / "swift"))
+    result = subprocess.run(command, cwd=ROOT, env=environment, text=True, capture_output=True)
    if result.returncode != 0:
        raise SystemExit(result.stdout + result.stderr)
    print(result.stdout.strip())
@@ -8,13 +8,18 @@ import re
 import shutil
 import subprocess
 import tempfile
+import os


 ROOT = pathlib.Path(__file__).resolve().parents[1]


 def run(command: list[str], directory: pathlib.Path) -> None:
-    result = subprocess.run(command, cwd=directory, text=True, capture_output=True, check=False)
+    environment = os.environ.copy()
+    cache_root = pathlib.Path(tempfile.gettempdir()) / "versevdi-protocol-module-cache"
+    environment.setdefault("CLANG_MODULE_CACHE_PATH", str(cache_root / "clang"))
+    environment.setdefault("SWIFT_MODULECACHE_PATH", str(cache_root / "swift"))
+    result = subprocess.run(command, cwd=directory, env=environment, text=True, capture_output=True, check=False)
    if result.returncode != 0:
        raise RuntimeError("%s\n%s%s" % (" ".join(command), result.stdout, result.stderr))

@@ -58,21 +63,42 @@ def main() -> int:
        swift.write_text(
            """import Foundation

+let video = try VideoProfile(codec: "h264", bitDepth: 8, chromaSubsampling: "4:2:0", colorSpace: "bt709-limited", transferFunction: "sdr")
+let hevc = try VideoProfile(codec: "hevc", bitDepth: 8, chromaSubsampling: "4:2:0", colorSpace: "bt709-limited", transferFunction: "sdr")
+let audio = try AudioProfile(codec: "opus", sampleRateHz: 48000, channels: 2, channelLayout: "stereo", packetDurationMs: 5)
+let display = try DisplayMode(resolutionWidth: 2560, resolutionHeight: 1440, fps: 120)
+let adjustment = try SessionAdjustment(displayReason: "none", bitrateReason: "none")
+let descriptor = try SelectedSessionDescriptor(videoProfile: video, audioProfile: audio, displayMode: display, bitrateTargetKbps: 40000, bitrateMaximumKbps: 50000, adjustment: adjustment, mediaTimestampBasis: "gateway-send-wall-clock-ms")
+let operationId = "12345678-1234-1234-1234-123456789abc"
+_ = try GatewayQualityWorkRequest(version: "1", sessionId: "session", gatewayId: "gateway", reconnectSequence: 2, acquisition: "poll", operationId: nil, revision: nil, leaseGeneration: nil, currentAppliedRevision: nil)
+_ = try GatewayQualityWorkRequest(version: "1", sessionId: "session", gatewayId: "gateway", reconnectSequence: 2, acquisition: "prompt", operationId: operationId, revision: 7, leaseGeneration: nil, currentAppliedRevision: nil)
+_ = try GatewayQualityWorkRequest(version: "1", sessionId: "session", gatewayId: "gateway", reconnectSequence: 2, acquisition: "observation", operationId: operationId, revision: 7, leaseGeneration: 3, currentAppliedRevision: 6)
+do {
+    _ = try GatewayQualityWorkRequest(version: "1", sessionId: "session", gatewayId: "gateway", reconnectSequence: 2, acquisition: "poll", operationId: operationId, revision: 7, leaseGeneration: nil, currentAppliedRevision: nil)
+    fatalError("poll accepted unknown operation coordinates")
+} catch { }
+_ = try GatewayQualityAck(version: "1", sessionId: "session", gatewayId: "gateway", reconnectSequence: 2, operationId: operationId, revision: 7, leaseGeneration: 3, outcome: "applied", currentAppliedRevision: 7, failureCode: nil)
+_ = try GatewayQualityAck(version: "1", sessionId: "session", gatewayId: "gateway", reconnectSequence: 2, operationId: operationId, revision: 7, leaseGeneration: 3, outcome: "proven_prior", currentAppliedRevision: 6, failureCode: nil)
+_ = try GatewayQualityAck(version: "1", sessionId: "session", gatewayId: "gateway", reconnectSequence: 2, operationId: operationId, revision: 7, leaseGeneration: 3, outcome: "unknown", currentAppliedRevision: nil, failureCode: nil)
+do {
+    _ = try GatewayQualityAck(version: "1", sessionId: "session", gatewayId: "gateway", reconnectSequence: 2, operationId: operationId, revision: 7, leaseGeneration: 3, outcome: "applied", currentAppliedRevision: 6, failureCode: nil)
+    fatalError("applied ack accepted a contradictory revision")
+} catch { }
 let capability = try CapabilityProfile(
    transport: "quic-tls13", framing: "datagram-v1", media: "encoded",
-    audio: "encoded", sourceRateControl: "server", clientDecode: ["h264-opus"]
+    sourceRateControl: "server", videoProfiles: [video], audioProfiles: [audio]
 )
 guard currentWireVersion == "2", nMinus1WireVersion == "1", nMinus2WireVersion == "0" else {
    fatalError("unexpected control wire compatibility declaration")
 }
 _ = try CapabilityProfile(
    transport: "quic-tls13", framing: "datagram-v2", media: "encoded",
-    audio: "encoded", sourceRateControl: "server", clientDecode: ["h264-opus"]
+    sourceRateControl: "server", videoProfiles: [video], audioProfiles: [audio]
 )
 do {
    _ = try CapabilityProfile(
        transport: "quic-tls13", framing: "datagram-v3", media: "encoded",
-        audio: "encoded", sourceRateControl: "server", clientDecode: ["h264-opus"]
+        sourceRateControl: "server", videoProfiles: [video], audioProfiles: [audio]
    )
    fatalError("unregistered framing was accepted")
 } catch { }
@@ -82,7 +108,7 @@ let request = try TunnelAdmissionRequest(
    clientNonce: String(repeating: "n", count: 16), deviceSignature: String(repeating: "s", count: 86), capabilities: capability
 )
 _ = request
-let transcript = "versevdi/tunnel-admission/v17:session7:gateway8:audience43:" + String(repeating: "g", count: 43) + "1:016:" + String(repeating: "n", count: 16) + "10:quic-tls1311:datagram-v17:encoded7:encoded6:server1:19:h264-opus"
+let transcript = "versevdi/tunnel-admission/v17:session7:gateway8:audience43:" + String(repeating: "g", count: 43) + "1:016:" + String(repeating: "n", count: 16) + "10:quic-tls1311:datagram-v17:encoded6:server1:11:14:h2641:85:4:2:013:bt709-limited3:sdr4:opus5:480001:26:stereo1:5"
 guard String(data: request.deviceAdmissionTranscript(), encoding: .utf8) == transcript else {
    fatalError("unexpected device admission transcript")
 }
@@ -126,18 +152,18 @@ for (name, field, serverID, principalID, deviceID, challenge, expiry) in invalid
 }
 let incompatible = try CapabilityProfile(
    transport: "quic-tls13", framing: "datagram-v1", media: "encoded",
-    audio: "encoded", sourceRateControl: "server", clientDecode: ["hevc-opus"]
+    sourceRateControl: "server", videoProfiles: [hevc], audioProfiles: [audio]
 )
 let gatewayCapability = try CapabilityProfile(
    transport: "quic-tls13", framing: "datagram-v1", media: "encoded",
-    audio: "encoded", sourceRateControl: "server", clientDecode: ["hevc-opus", "h264-opus"]
+    sourceRateControl: "server", videoProfiles: [hevc, video], audioProfiles: [audio]
 )
 do {
    guard try CapabilityProfile.intersection([capability, capability]) == capability else {
        fatalError("matching capability profiles did not intersect")
    }
 } catch { fatalError("matching capability profiles did not intersect") }
-guard try CapabilityProfile.intersection([gatewayCapability, capability]).clientDecode == ["h264-opus"] else {
+guard try CapabilityProfile.intersection([gatewayCapability, capability]).videoProfiles == [video] else {
    fatalError("ordered registered profile intersection changed")
 }
 do {
@@ -165,17 +191,35 @@ for invalid in [
 }
 let clientAuthority = try ClientSessionAuthority(
    version: "1", sessionId: "session", gatewayId: "gateway", audience: "audience",
-    reconnectSequence: 2, expiresAt: "2099-01-01T00:00:00Z", capabilities: capability
+    reconnectSequence: 2, expiresAt: "2099-01-01T00:00:00Z", capabilities: capability, selectedDescriptor: descriptor
 )
 let clientAuthorityJSON = try clientAuthority.encodeJSON()
 let clientAuthorityObject = try JSONSerialization.jsonObject(with: clientAuthorityJSON) as! [String: Any]
 guard Set(clientAuthorityObject.keys) == Set([
-    "version", "session_id", "gateway_id", "audience", "reconnect_sequence", "expires_at", "capabilities"
+    "version", "session_id", "gateway_id", "audience", "reconnect_sequence", "expires_at", "capabilities", "selected_descriptor"
 ]), !String(data: clientAuthorityJSON, encoding: .utf8)!.contains("provider_") else {
    fatalError("client authority was not exactly provider-free")
 }
 _ = try ClientSessionAuthority.decodeJSON(clientAuthorityJSON)
-for field in ["version", "session_id", "gateway_id", "audience", "reconnect_sequence", "expires_at", "capabilities"] {
+let duplicateCapability = Data(#"{"transport":"quic-tls13","transport":"quic-tls13","framing":"datagram-v1","media":"encoded","source_rate_control":"server","video_profiles":[{"codec":"h264","bit_depth":8,"chroma_subsampling":"4:2:0","color_space":"bt709-limited","transfer_function":"sdr"}],"audio_profiles":[{"codec":"opus","sample_rate_hz":48000,"channels":2,"channel_layout":"stereo","packet_duration_ms":5}]}"#.utf8)
+do {
+    _ = try CapabilityProfile.decodeJSON(duplicateCapability)
+    fatalError("capability accepted duplicate JSON keys")
+} catch { }
+do {
+    _ = try CapabilityProfile.decodeJSON(Data(repeating: 32, count: 1_048_577))
+    fatalError("capability accepted oversized JSON")
+} catch let error as ContractValidationError {
+    guard error.code == "payload_too_large" else { fatalError("oversized JSON was not rejected before parsing") }
+}
+let deeplyNested = Data((String(repeating: "[", count: 65) + "null" + String(repeating: "]", count: 65)).utf8)
+do {
+    _ = try CapabilityProfile.decodeJSON(deeplyNested)
+    fatalError("capability accepted over-deep JSON")
+} catch let error as ContractValidationError {
+    guard error.code == "nesting_too_deep" else { fatalError("over-deep JSON was not rejected before decoding") }
+}
+for field in ["version", "session_id", "gateway_id", "audience", "reconnect_sequence", "expires_at", "capabilities", "selected_descriptor"] {
    var missing = clientAuthorityObject
    missing.removeValue(forKey: field)
    do {
@@ -217,7 +261,7 @@ do {
    )
    fatalError("invalid allocation bounds were accepted")
 } catch { }
-let displayMode = try DisplayMode(resolutionWidth: 2560, resolutionHeight: 1440, fps: 120)
+let displayMode = display
 for invalid in [
    { try DisplayMode(resolutionWidth: 319, resolutionHeight: 1440, fps: 120) },
    { try DisplayMode(resolutionWidth: 2560, resolutionHeight: 199, fps: 120) },
@@ -230,14 +274,14 @@ for invalid in [
 }
 let policyFreeV2Request = try SessionRequest(
    clientDeviceId: "device-1", deviceKeyId: "key-1", poolId: "pool-1",
-    idempotencyKey: "request-1", requestedDisplayMode: nil
+    idempotencyKey: "request-1", videoProfiles: [video], bitratePreference: try BitratePreference(mode: "auto", targetKbps: nil), requestedDisplayMode: nil
 ).encodeJSON()
 guard !String(data: policyFreeV2Request, encoding: .utf8)!.contains("requested_display_mode") else {
    fatalError("wire-v2 request encoded an absent display mode")
 }
 let displayRequest = try SessionRequest(
    clientDeviceId: "device-1", deviceKeyId: "key-1", poolId: "pool-1",
-    idempotencyKey: "request-1", requestedDisplayMode: displayMode
+    idempotencyKey: "request-1", videoProfiles: [video], bitratePreference: try BitratePreference(mode: "explicit", targetKbps: 40000), requestedDisplayMode: displayMode
 )
 guard try SessionRequest.decodeJSON(displayRequest.encodeJSON()).requestedDisplayMode == displayMode else {
    fatalError("display mode did not round-trip")
@@ -295,14 +339,14 @@ for expiresAt in ["2099-01-01T00:00:00+00:00", "2099-01-01T00:00:00.100Z"] {
    } catch { }
 }
 let streamPolicy = try ProviderStreamPolicy(
-    resolutionWidth: 2560, resolutionHeight: 1440, fps: 120,
-    codec: "HEVC", bitrateKbps: 40000, audioEnabled: true
+    videoProfile: hevc, audioProfile: audio, displayMode: displayMode,
+    bitrateTargetKbps: 40000, bitrateMaximumKbps: 50000
 )
-guard streamPolicy.codec == "HEVC" else { fatalError("stream policy changed") }
+guard streamPolicy.videoProfile == hevc else { fatalError("stream policy changed") }
 for invalid in [
-    { try ProviderStreamPolicy(resolutionWidth: 319, resolutionHeight: 1440, fps: 120, codec: "HEVC", bitrateKbps: 40000, audioEnabled: true) },
-    { try ProviderStreamPolicy(resolutionWidth: 2560, resolutionHeight: 1440, fps: 241, codec: "HEVC", bitrateKbps: 40000, audioEnabled: true) },
-    { try ProviderStreamPolicy(resolutionWidth: 2560, resolutionHeight: 1440, fps: 120, codec: "VP9", bitrateKbps: 40000, audioEnabled: true) },
+    { try ProviderStreamPolicy(videoProfile: video, audioProfile: audio, displayMode: try DisplayMode(resolutionWidth: 319, resolutionHeight: 1440, fps: 120), bitrateTargetKbps: 40000, bitrateMaximumKbps: 50000) },
+    { try ProviderStreamPolicy(videoProfile: video, audioProfile: audio, displayMode: displayMode, bitrateTargetKbps: 50001, bitrateMaximumKbps: 50000) },
+    { try ProviderStreamPolicy(videoProfile: try VideoProfile(codec: "vp9", bitDepth: 8, chromaSubsampling: "4:2:0", colorSpace: "bt709-limited", transferFunction: "sdr"), audioProfile: audio, displayMode: displayMode, bitrateTargetKbps: 40000, bitrateMaximumKbps: 50000) },
 ] {
    do {
        _ = try invalid()
@@ -363,17 +407,32 @@ fn main() {
    assert_eq!(CURRENT_WIRE_VERSION, "2");
    assert_eq!(N_MINUS_1_WIRE_VERSION, "1");
    assert_eq!(N_MINUS_2_WIRE_VERSION, "0");
+    let video = VideoProfile::new("h264".into(), 8, "4:2:0".into(), "bt709-limited".into(), "sdr".into()).unwrap();
+    let hevc = VideoProfile::new("hevc".into(), 8, "4:2:0".into(), "bt709-limited".into(), "sdr".into()).unwrap();
+    let audio = AudioProfile::new("opus".into(), 48000, 2, "stereo".into(), 5).unwrap();
+    let display = DisplayMode::new(2560, 1440, 120).unwrap();
+    let adjustment = SessionAdjustment::new("none".into(), "none".into()).unwrap();
+    let descriptor = SelectedSessionDescriptor::new(video.clone(), audio.clone(), display.clone(), 40000, 50000, adjustment, "gateway-send-wall-clock-ms".into()).unwrap();
+    let operation_id = "12345678-1234-1234-1234-123456789abc".to_string();
+    assert!(GatewayQualityWorkRequest::new("1".into(), "session".into(), "gateway".into(), 2, "poll".into(), None, None, None, None).is_ok());
+    assert!(GatewayQualityWorkRequest::new("1".into(), "session".into(), "gateway".into(), 2, "prompt".into(), Some(operation_id.clone()), Some(7), None, None).is_ok());
+    assert!(GatewayQualityWorkRequest::new("1".into(), "session".into(), "gateway".into(), 2, "observation".into(), Some(operation_id.clone()), Some(7), Some(3), Some(6)).is_ok());
+    assert!(GatewayQualityWorkRequest::new("1".into(), "session".into(), "gateway".into(), 2, "poll".into(), Some(operation_id.clone()), Some(7), None, None).is_err());
+    assert!(GatewayQualityAck::new("1".into(), "session".into(), "gateway".into(), 2, operation_id.clone(), 7, 3, "applied".into(), Some(7), None).is_ok());
+    assert!(GatewayQualityAck::new("1".into(), "session".into(), "gateway".into(), 2, operation_id.clone(), 7, 3, "proven_prior".into(), Some(6), None).is_ok());
+    assert!(GatewayQualityAck::new("1".into(), "session".into(), "gateway".into(), 2, operation_id.clone(), 7, 3, "unknown".into(), None, None).is_ok());
+    assert!(GatewayQualityAck::new("1".into(), "session".into(), "gateway".into(), 2, operation_id, 7, 3, "applied".into(), Some(6), None).is_err());
    let capabilities = CapabilityProfile::new(
        "quic-tls13".into(), "datagram-v1".into(), "encoded".into(),
-        "encoded".into(), "server".into(), vec!["h264-opus".into()],
+        "server".into(), vec![video.clone()], vec![audio.clone()],
    ).unwrap();
    assert!(CapabilityProfile::new(
        "quic-tls13".into(), "datagram-v2".into(), "encoded".into(),
-        "encoded".into(), "server".into(), vec!["h264-opus".into()],
+        "server".into(), vec![video.clone()], vec![audio.clone()],
    ).is_ok());
    assert!(CapabilityProfile::new(
        "quic-tls13".into(), "datagram-v3".into(), "encoded".into(),
-        "encoded".into(), "server".into(), vec!["h264-opus".into()],
+        "server".into(), vec![video.clone()], vec![audio.clone()],
    ).is_err());
    let request = TunnelAdmissionRequest::new(
        "1".into(), "session".into(), "gateway".into(), "audience".into(),
@@ -381,7 +440,7 @@ fn main() {
    ).unwrap();
    let transcript = "versevdi/tunnel-admission/v17:session7:gateway8:audience43:".to_string()
        + &"g".repeat(43) + "1:016:" + &"n".repeat(16)
-        + "10:quic-tls1311:datagram-v17:encoded7:encoded6:server1:19:h264-opus";
+        + "10:quic-tls1311:datagram-v17:encoded6:server1:11:14:h2641:85:4:2:013:bt709-limited3:sdr4:opus5:480001:26:stereo1:5";
    assert_eq!(request.device_admission_transcript(), transcript.into_bytes());
    let proof_server_id = vec![1u8; 16];
    let proof_principal_id = vec![2u8; 16];
@@ -423,26 +482,26 @@ fn main() {
    ).is_err());
    let client_authority = ClientSessionAuthority::new(
        "1".into(), "session".into(), "gateway".into(), "audience".into(), 2,
-        "2099-01-01T00:00:00Z".into(), capabilities.clone(),
+        "2099-01-01T00:00:00Z".into(), capabilities.clone(), descriptor.clone(),
    ).unwrap();
    assert_eq!(client_authority.sessionId(), "session");
    assert_eq!(client_authority.capabilities(), &capabilities);
    assert!(ClientSessionAuthority::new(
        "1".into(), "session".into(), "gateway".into(), "audience".into(), 2,
-        "not-a-time".into(), capabilities.clone(),
+        "not-a-time".into(), capabilities.clone(), descriptor.clone(),
    ).is_err());
    assert!(intersect_capability_profiles(&[capabilities.clone(), capabilities.clone()]).is_ok());
    let incompatible = CapabilityProfile::new(
        "quic-tls13".into(), "datagram-v1".into(), "encoded".into(),
-        "encoded".into(), "server".into(), vec!["hevc-opus".into()],
+        "server".into(), vec![hevc.clone()], vec![audio.clone()],
    ).unwrap();
    let gateway_capability = CapabilityProfile::new(
        "quic-tls13".into(), "datagram-v1".into(), "encoded".into(),
-        "encoded".into(), "server".into(), vec!["hevc-opus".into(), "h264-opus".into()],
+        "server".into(), vec![hevc.clone(), video.clone()], vec![audio.clone()],
    ).unwrap();
    assert_eq!(
-        intersect_capability_profiles(&[gateway_capability, capabilities.clone()]).unwrap().clientDecode(),
-        &vec!["h264-opus".to_string()],
+        intersect_capability_profiles(&[gateway_capability, capabilities.clone()]).unwrap().videoProfiles(),
+        &vec![video.clone()],
    );
    assert!(intersect_capability_profiles(&[capabilities, incompatible]).is_err());
    assert!(AllocationPolicy::new(
@@ -454,11 +513,13 @@ fn main() {
    assert!(DisplayMode::new(2560, 1440, 241).is_err());
    let policy_free_v2_request = SessionRequest::new(
        "device-1".into(), "key-1".into(), "pool-1".into(), "request-1".into(),
+        vec![video.clone()], BitratePreference::new("auto".into(), None).unwrap(),
        None,
    ).unwrap();
    assert!(policy_free_v2_request.requestedDisplayMode().is_none());
    let display_request = SessionRequest::new(
        "device-1".into(), "key-1".into(), "pool-1".into(), "request-1".into(),
+        vec![video.clone()], BitratePreference::new("explicit".into(), Some(40000)).unwrap(),
        Some(display_mode.clone()),
    ).unwrap();
    assert_eq!(display_request.requestedDisplayMode(), &Some(display_mode));
@@ -486,17 +547,13 @@ fn main() {
        ).is_err());
    }
    assert!(ProviderStreamPolicy::new(
-        2560, 1440, 120, "HEVC".into(), 40000, true,
+        hevc.clone(), audio.clone(), display.clone(), 40000, 50000,
    ).is_ok());
+    assert!(DisplayMode::new(319, 1440, 120).is_err());
    assert!(ProviderStreamPolicy::new(
-        319, 1440, 120, "HEVC".into(), 40000, true,
-    ).is_err());
-    assert!(ProviderStreamPolicy::new(
-        2560, 1440, 241, "HEVC".into(), 40000, true,
-    ).is_err());
-    assert!(ProviderStreamPolicy::new(
-        2560, 1440, 120, "VP9".into(), 40000, true,
+        video.clone(), audio.clone(), display.clone(), 50001, 50000,
    ).is_err());
+    assert!(VideoProfile::new("vp9".into(), 8, "4:2:0".into(), "bt709-limited".into(), "sdr".into()).is_err());
    assert!(GatewayTelemetry::new(
        1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, "ready".into(),
    ).is_ok());
@@ -524,7 +581,8 @@ fn main() {
            )
        run(["rustc", str(rust), "-o", str(workspace / "rust-contracts")], ROOT)
        run([str(workspace / "rust-contracts")], ROOT)
-        expected_protobuf_fields = [
+        expected_protobuf_messages = {
+            "ClientSessionAuthority": [
                ("version", 1),
                ("session_id", 2),
                ("gateway_id", 3),
@@ -532,11 +590,57 @@ fn main() {
                ("reconnect_sequence", 5),
                ("expires_at", 6),
                ("capabilities", 7),
-        ]
-        actual_protobuf_fields = protobuf_message_fields("ClientSessionAuthority")
+                ("selected_descriptor", 8),
+            ],
+            "GatewayQualityWorkRequest": [
+                ("version", 1),
+                ("session_id", 2),
+                ("gateway_id", 3),
+                ("reconnect_sequence", 4),
+                ("operation_id", 5),
+                ("revision", 6),
+                ("current_applied_revision", 7),
+                ("acquisition", 8),
+                ("lease_generation", 9),
+            ],
+            "GatewayQualityWork": [
+                ("version", 1),
+                ("session_id", 2),
+                ("gateway_id", 3),
+                ("reconnect_sequence", 4),
+                ("operation_id", 5),
+                ("revision", 6),
+                ("lease_expires_at", 7),
+                ("selected_descriptor", 8),
+                ("current_applied_revision", 9),
+                ("lease_generation", 10),
+            ],
+            "GatewayQualityAck": [
+                ("version", 1),
+                ("session_id", 2),
+                ("gateway_id", 3),
+                ("reconnect_sequence", 4),
+                ("operation_id", 5),
+                ("revision", 6),
+                ("outcome", 7),
+                ("current_applied_revision", 8),
+                ("failure_code", 9),
+                ("lease_generation", 10),
+            ],
+            "GatewayStopWorkRequest": [
+                ("version", 1),
+                ("session_id", 2),
+                ("gateway_id", 3),
+                ("reconnect_sequence", 4),
+                ("operation_id", 5),
+                ("acquisition", 6),
+            ],
+        }
+        for message, expected_protobuf_fields in expected_protobuf_messages.items():
+            actual_protobuf_fields = protobuf_message_fields(message)
            if actual_protobuf_fields != expected_protobuf_fields:
                raise RuntimeError(
-                f"ClientSessionAuthority protobuf fields = {actual_protobuf_fields}; "
+                    f"{message} protobuf fields = {actual_protobuf_fields}; "
                    f"want {expected_protobuf_fields}"
                )
        rust_unknown = workspace / "unknown.rs"
@@ -12,6 +12,17 @@ import sys
 ROOT = pathlib.Path(__file__).resolve().parents[1]


+def matches_outcome_branch(instance: dict[str, object], branch: dict[str, object]) -> bool:
+    required = branch.get("required", [])
+    if not all(field in instance for field in required):
+        return False
+    outcome = branch.get("properties", {}).get("outcome", {}).get("const")
+    if instance.get("outcome") != outcome:
+        return False
+    forbidden = branch.get("not", {}).get("required", [])
+    return not all(field in instance for field in forbidden) if forbidden else True
+
+
 def main() -> int:
    schema_path = ROOT / "schemas/control-v1.schema.json"
    schema = json.loads(schema_path.read_text(encoding="utf-8"))
@@ -39,6 +50,65 @@ def main() -> int:
    feature_registry = json.loads((ROOT / "registries/features.json").read_text(encoding="utf-8"))
    registered_features = {entry["id"] for entry in feature_registry["features"]}
    assert {"control.v1", "control.v2", "display.request.v1", "input.absolute.v1", "input.scroll.v1"}.issubset(registered_features)
+    assert {"video.profile.v1", "session.quality.v1", "session.stop.v1", "controller.arrival.v1"}.issubset(registered_features)
+
+    assert defs["VideoProfile"]["required"] == ["codec", "bit_depth", "chroma_subsampling", "color_space", "transfer_function"]
+    assert defs["AudioProfile"]["required"] == ["codec", "sample_rate_hz", "channels", "channel_layout", "packet_duration_ms"]
+    assert defs["CapabilityProfile"]["required"] == ["transport", "framing", "media", "source_rate_control", "video_profiles", "audio_profiles"]
+    assert defs["CapabilityProfile"]["properties"]["video_profiles"] == {"type": "array", "minItems": 1, "maxItems": 12, "uniqueItems": True, "items": {"$ref": "#/$defs/VideoProfile"}}
+    assert defs["CapabilityProfile"]["properties"]["audio_profiles"] == {"type": "array", "minItems": 1, "maxItems": 1, "uniqueItems": True, "items": {"$ref": "#/$defs/AudioProfile"}}
+    assert defs["SessionRequest"]["required"][-2:] == ["video_profiles", "bitrate_preference"]
+    assert defs["ReconnectRequest"]["required"][-1] == "display_relaunch_confirmed"
+    assert defs["AssignedDesktop"]["required"][-1] == "quality_limits"
+    assert defs["EntitledPool"]["required"][-1] == "quality_limits"
+    for owner in ("SessionAuthority", "ClientSessionAuthority"):
+        assert defs[owner]["required"][-1] == "selected_descriptor"
+    assert defs["ConnectionManifest"]["required"][-1] == "selected_descriptor"
+    quality_request = defs["GatewayQualityWorkRequest"]
+    assert quality_request["required"] == ["version", "session_id", "gateway_id", "reconnect_sequence", "acquisition"]
+    assert quality_request["properties"]["acquisition"]["enum"] == ["poll", "prompt", "observation"]
+    assert quality_request["properties"]["lease_generation"]["minimum"] == 1
+    assert defs["GatewayStopWorkRequest"]["required"] == ["version", "session_id", "gateway_id", "reconnect_sequence", "acquisition"]
+    assert defs["GatewayQualityWork"]["required"][-3:] == ["lease_generation", "lease_expires_at", "selected_descriptor"]
+    quality_ack = defs["GatewayQualityAck"]
+    assert quality_ack["required"][-3:] == ["revision", "lease_generation", "outcome"]
+    assert quality_ack["properties"]["outcome"]["enum"] == ["applied", "proven_prior", "unknown"]
+    assert quality_ack["description"] == (
+        "Outcome invariants: applied requires current_applied_revision equal to revision; "
+        "proven_prior requires current_applied_revision strictly less than revision; "
+        "unknown forbids current_applied_revision and makes no applied-revision assertion."
+    )
+    assert quality_ack["oneOf"] == [
+        {"properties": {"outcome": {"const": "applied"}}, "required": ["current_applied_revision"]},
+        {"properties": {"outcome": {"const": "proven_prior"}}, "required": ["current_applied_revision"]},
+        {"properties": {"outcome": {"const": "unknown"}}, "not": {"required": ["current_applied_revision"]}},
+    ]
+    ack_branches = quality_ack["oneOf"]
+    for valid_ack in (
+        {"outcome": "applied", "current_applied_revision": 7},
+        {"outcome": "proven_prior", "current_applied_revision": 6},
+        {"outcome": "unknown"},
+    ):
+        assert sum(matches_outcome_branch(valid_ack, branch) for branch in ack_branches) == 1, valid_ack
+    for invalid_ack in (
+        {"outcome": "applied"},
+        {"outcome": "proven_prior"},
+        {"outcome": "unknown", "current_applied_revision": 6},
+    ):
+        assert not any(matches_outcome_branch(invalid_ack, branch) for branch in ack_branches), invalid_ack
+
+    operation_id_pattern = r"^(?!00000000-0000-0000-0000-000000000000$)[0-9a-f]{8}-[0-9a-f]{4}-[0-9a-f]{4}-[0-9a-f]{4}-[0-9a-f]{12}$"
+    canonical_time_pattern = r"^[0-9]{4}-[0-9]{2}-[0-9]{2}T[0-9]{2}:[0-9]{2}:[0-9]{2}(?:\.[0-9]{0,8}[1-9])?Z$"
+    for definition in ("QualityChangeOperation", "StopOperation", "GatewayQualityWorkRequest", "GatewayQualityWork", "GatewayQualityAck", "GatewayStopWorkRequest", "GatewayStopWork", "GatewayStopAck"):
+        assert defs[definition]["properties"]["operation_id"]["pattern"] == operation_id_pattern, definition
+        assert defs[definition]["x-max-bytes"] == 16384, definition
+    for definition, fields in {
+        "QualityChangeOperation": ("created_at", "deadline_at", "updated_at"),
+        "StopOperation": ("created_at", "deadline_at", "updated_at"),
+        "GatewayQualityWork": ("lease_expires_at",),
+    }.items():
+        for field in fields:
+            assert defs[definition]["properties"][field]["pattern"] == canonical_time_pattern, (definition, field)

    display_mode = defs["DisplayMode"]
    assert display_mode["required"] == ["resolution_width", "resolution_height", "fps"]
@@ -113,6 +183,17 @@ def main() -> int:
    assert "native_identity" not in native_missing_fixture
    tunnel_credential_fixture = json.loads((ROOT / "fixtures/valid/native-tunnel-credential.json").read_text(encoding="utf-8"))
    assert set(tunnel_credential_fixture) == set(tunnel_credential["required"])
+    valid_fixture_contracts = {
+        "fixtures/valid/session-request.json": "SessionRequest",
+        "fixtures/valid/selected-session-descriptor.json": "SelectedSessionDescriptor",
+        "fixtures/valid/session-quality-limits.json": "SessionQualityLimits",
+    }
+    for relative, definition in valid_fixture_contracts.items():
+        fixture = json.loads((ROOT / relative).read_text(encoding="utf-8"))
+        assert set(fixture) == set(defs[definition]["required"]), (relative, definition)
+    assert set(json.loads((ROOT / "fixtures/invalid/capability-rc5-opaque.json").read_text())) & {"audio", "client_decode"} == {"audio", "client_decode"}
+    assert "video_profiles" not in json.loads((ROOT / "fixtures/invalid/session-request-rc5.json").read_text())
+    assert set(json.loads((ROOT / "fixtures/invalid/provider-stream-policy-rc5.json").read_text())) == {"resolution_width", "resolution_height", "fps", "codec", "bitrate_kbps", "audio_enabled"}

    expected_header = "id\tversion\tkind\tinput\texpected"
    ids = set()
@@ -139,10 +220,64 @@ def main() -> int:
        fixture_hash.update((ROOT / relative).read_bytes())
        fixture_hash.update(b"\0")
    assert fixture_manifest["corpus_sha256"] == fixture_hash.hexdigest()
+    json_fixture_paths = sorted(
+        path.relative_to(ROOT).as_posix()
+        for directory in (ROOT / "fixtures/valid", ROOT / "fixtures/invalid")
+        for path in directory.glob("*.json")
+    )
+    assert fixture_manifest["json_files"] == json_fixture_paths
+    json_fixture_hash = hashlib.sha256()
+    for relative in json_fixture_paths:
+        json_fixture_hash.update(relative.encode("utf-8"))
+        json_fixture_hash.update(b"\0")
+        json_fixture_hash.update((ROOT / relative).read_bytes())
+        json_fixture_hash.update(b"\0")
+    assert fixture_manifest["json_corpus_sha256"] == json_fixture_hash.hexdigest()

    openapi = (ROOT / "openapi/control-v1.yaml").read_text(encoding="utf-8")
    assert "openapi: 3.1.0" in openapi
    assert "/api/v1/auth/refresh:" in openapi and "/api/v1/resources:" in openapi and "/api/v1/events:" in openapi
+    for route in (
+        "/api/v1/session-quality-limits:",
+        "/api/v1/session-quality-limits/assignments/{assignment_id}:",
+        "/api/v1/session-quality-limits/pools/{pool_id}:",
+        "/api/v1/admin/entitlements/{entitlement_id}/display-limit-override:",
+        "/api/v1/broker/sessions/{session_id}/quality-changes:",
+        "/api/v1/broker/sessions/{session_id}/quality-changes/{operation_id}:",
+        "/api/v1/broker/sessions/{session_id}/stop-operations:",
+        "/api/v1/broker/sessions/{session_id}/stop-operations/{operation_id}:",
+        "/api/v1/gateway/quality-work:",
+        "/api/v1/gateway/quality-ack:",
+        "/api/v1/gateway/stop-work:",
+        "/api/v1/gateway/stop-ack:",
+    ):
+        assert route in openapi, route
+    for operation_id in (
+        "getSessionQualityLimits", "getAssignmentSessionQualityLimits", "getPoolSessionQualityLimits",
+        "createSessionQualityChange", "getSessionQualityChange", "createSessionStopOperation", "getSessionStopOperation",
+    ):
+        operation = openapi.split(f"      operationId: {operation_id}\n", 1)[1].split("      responses:\n", 1)[0]
+        assert "nativeBearer: []" in operation and "browserSession" not in operation, operation_id
+    for operation_id in (
+        "acquireGatewayQualityWork", "acknowledgeGatewayQualityWork", "acquireGatewayStopWork", "acknowledgeGatewayStopWork",
+    ):
+        operation = openapi.split(f"      operationId: {operation_id}\n", 1)[1].split("      responses:\n", 1)[0]
+        assert "gatewayMutualTLS: []" in operation and "nativeBearer" not in operation and "browserSession" not in operation, operation_id
+        assert "certificate identity MUST match" in operation, operation_id
+        assert "Maximum JSON body: 16384 bytes." in operation, operation_id
+    quality_acquisition = openapi.split("      operationId: acquireGatewayQualityWork\n", 1)[1].split("      responses:\n", 1)[0]
+    assert "`poll` acquisition omits unknown operation coordinates" in quality_acquisition
+    assert "coordinates MUST match exactly" in quality_acquisition
+    quality_acknowledgement = openapi.split("      operationId: acknowledgeGatewayQualityWork\n", 1)[1].split("      responses:\n", 1)[0]
+    assert "Stale lease generations MUST be rejected" in quality_acknowledgement
+    assert "`applied` requires `current_applied_revision == revision`" in quality_acknowledgement
+    assert "`proven_prior` requires `current_applied_revision < revision`" in quality_acknowledgement
+    assert "`unknown` forbids `current_applied_revision`" in quality_acknowledgement
+    for operation_id in ("createSessionQualityChange", "getSessionQualityChange", "createSessionStopOperation", "getSessionStopOperation"):
+        operation = openapi.split(f"      operationId: {operation_id}\n", 1)[1].split("      responses:\n", 1)[0]
+        assert "owning principal and active device/key" in operation, operation_id
+    assert openapi.count("Maximum JSON body: 16384 bytes.") >= 8
+    assert operation_id_pattern in openapi
    assert "provider_url" not in openapi and "vm_address" not in openapi
    session_endpoint = openapi.split("  /api/v1/auth/session:", 1)[1].split("\n  /api/", 1)[0]
    assert "$defs/BrowserAuthenticatedSession" in session_endpoint
@@ -172,6 +307,9 @@ def main() -> int:
          browserCsrfCookie: []
          browserCsrfHeader: []
 """
+    admin_override = openapi.split("      operationId: updateEntitlementDisplayLimitOverride\n", 1)[1].split("      responses:\n", 1)[0]
+    assert browser_requirement.removeprefix("      ") in admin_override
+    assert "Maximum JSON body: 16384 bytes." in admin_override
    for operation_id in (
        "issueReauthenticationGrant", "logoutSession", "registerDevice", "proveDevice", "revokeDevice",
        "requestBrokerSession", "allocateBrokerSession", "reconnectBrokerSession", "cancelBrokerSession",
@@ -44,6 +44,10 @@ def classify_input(raw: bytes) -> str:
        return "valid" if width and height and x < width and y < height else "invalid:field"
    if kind == 7:
        return "valid" if len(body) == 4 else "invalid:length"
+    if kind == 8:
+        if len(body) != 8:
+            return "invalid:length"
+        return "valid" if body[0] <= 15 and body[3] <= 3 else "invalid:field"
    return "invalid:kind"


@@ -68,6 +72,14 @@ def classify_feedback(raw: bytes) -> str:
            return "valid" if valid_fec_status(body) else "invalid:field"
        if kind == 3:
            return "valid" if not body else "invalid:length"
+        if kind == 4:
+            if len(body) != 24:
+                return "invalid:length"
+            return "valid" if any(body[:16]) and int.from_bytes(body[16:24], "big") > 0 else "invalid:field"
+        if kind == 5:
+            if len(body) != 16:
+                return "invalid:length"
+            return "valid" if any(body) else "invalid:field"
        return "invalid:type"
    if kind in (1, 2, 3):
        return "invalid:direction"
Author	SHA1	Message	Date
sechmachine	c3ea2f35c6	fix(protocol): align quality ack schema Verify Protocol / module (push) Successful in 1m21s Details Verify Protocol / verify (push) Successful in 1m2s Details	2026-08-13 07:53:35 +07:00
sechmachine	6e18bc9ee6	fix(protocol): fence gateway work recovery	2026-08-13 07:43:42 +07:00
sechmachine	8eacc4fda9	feat(protocol): freeze M4 native session RC6 contract	2026-08-13 07:18:03 +07:00
				`@@ -0,0 +1 @@`
				`{"transport":"quic-tls13","framing":"datagram-v2","media":"encoded","audio":"encoded","source_rate_control":"server","client_decode":["h264-opus"]}`
				`@@ -0,0 +1 @@`
				`{"version":"1","session_id":"session-1","gateway_id":"gateway-1","reconnect_sequence":2,"operation_id":"12345678-1234-1234-1234-123456789abc","revision":7,"lease_generation":3,"outcome":"applied","current_applied_revision":6}`
				`@@ -0,0 +1 @@`
				`{"resolution_width":1920,"resolution_height":1080,"fps":60,"codec":"H264","bitrate_kbps":20000,"audio_enabled":true}`
				`@@ -0,0 +1 @@`
				`{"operation_id":"12345678-1234-1234-1234-123456789abc","session_id":"session-1","revision":7,"state":"pending","requested_bitrate_preference":{"mode":"auto"},"effective_bitrate_kbps":20000,"governing_policy_version":"policy-1","session_version":2,"created_at":"2099-01-01T00:00:00.100Z","deadline_at":"2099-01-01T00:00:30Z","updated_at":"2099-01-01T00:00:00Z"}`
				`@@ -0,0 +1 @@`
				{"video_profile":{"codec":"h264","bit_depth":8,"chroma_subsampling":"4:2:0","color_space":"bt709-limited","transfer_function":"sdr"},"audio_profile":{"codec":"opus","sample_rate_hz":48000,"channels":2,"channel_layout":"stereo","packet_duration_ms":5},"display_mode":{"resolution_width":1920,"resolution_height":1080,"fps":60},"bitrate_target_kbps":20000,"bitrate_maximum_kbps":40000,"adjustment":{"display_reason":"none","bitrate_reason":"none"},"media_timestamp_basis":"gateway-send-wall-clock-ms","provider_identity":"forbidden"}
				`@@ -0,0 +1 @@`
				`{"client_device_id":"device-1","device_key_id":"key-1","pool_id":"pool-1","idempotency_key":"request-1"}`
				`@@ -0,0 +1 @@`
				`{"codec":"vp9","bit_depth":8,"chroma_subsampling":"4:2:0","color_space":"bt709-limited","transfer_function":"sdr"}`