docs(bdd): annotate UC-019 SERVICE_UNAVAILABLE wire-code rationale

pyproject.toml

@@ -42,6 +42,7 @@ dependencies = [
     "logfire>=4.16.0",
     "pydantic-ai-slim[google,openai,anthropic,cohere,mistral,groq]>=1.99.0",  # 1.99.0 fixes CVE-2026-46678 / GHSA-cqp8-fcvh-x7r3; use slim to avoid pydantic-ai meta-package pulling fastmcp>=3.3.0
     # Security patches for transitive dependencies
+    "mcp>=1.28.1",  # CVE-2026-59950 / GHSA-vj7q-gjh5-988w (via fastmcp)
     "pyjwt>=2.13.0",  # GHSA-752w-5fwx-jx9f; PYSEC-2026-175/177/178/179
     "filelock>=3.20.3",  # GHSA-qmgc-5h2g-mvrw
     "urllib3>=2.7.0",  # GHSA-38jv-5279-wg99 + GHSA-qccp-gfcp-xxvc + GHSA-mf9v-mfxr-j63j

tests/bdd/features/BR-UC-019-query-media-buys.feature

@@ -932,6 +932,9 @@ Feature: BR-UC-019 Query Media Buys
     And the suggestion should contain "omit" or "without the `account` filter"
     # BR-RULE-293 INV-5: validation fails -> no DB query; no partial result leak
 
+  # CORRECTED to AdCP 3.1.1 enums/error-code.json: SERVICE_UNAVAILABLE is on-wire;
+  # INTERNAL_ERROR is absent from the enum (off-wire). Implementation: src/core/exceptions.py
+  # INTERNAL_CODES collapses INTERNAL_ERROR -> SERVICE_UNAVAILABLE on the wire.
   @T-UC-019-partition-targeting-rehydration @partition @targeting_overlay @schema-v3.1
   Scenario Outline: targeting_overlay rehydration - <partition>
     Given the principal "buyer-001" owns media buy "mb-001" with package "pkg-001"
@@ -948,6 +951,10 @@ Feature: BR-UC-019 Query Media Buys
       | legacy_targeting_key                 | no targeting_overlay but legacy targeting {geo:['US']} | the package "pkg-001" targeting_overlay should be a Targeting object with geo ["US"]                                                                            |
       | rehydration_typeerror_partial_success | targeting_overlay set to the string 'not a dict'      | the package "pkg-001" targeting_overlay should be null and response.errors[] should include a SERVICE_UNAVAILABLE entry with message starting "TARGETING_REHYDRATION_FAILED:" |
 
+  # CORRECTED to AdCP 3.1.1 enums/error-code.json: SERVICE_UNAVAILABLE is on-wire;
+  # INTERNAL_ERROR is absent from the enum (off-wire). Implementation: src/core/exceptions.py
+  # INTERNAL_CODES collapses INTERNAL_ERROR -> SERVICE_UNAVAILABLE on the wire.
+  # graded: unit — tests/unit/test_get_media_buys.py (BDD errors[] steps not wired; scenario dormant/xfail)
   @T-UC-019-inv-294-3 @invariant @BR-RULE-294 @error @schema-v3.1
   Scenario: INV-3 holds - TypeError during Targeting instantiation yields non-fatal SERVICE_UNAVAILABLE + null overlay
     Given the principal "buyer-001" owns media buy "mb-001" with package "pkg-001"
@@ -1203,6 +1210,9 @@ Feature: BR-UC-019 Query Media Buys
       | sandbox absent in response (production account)         | targets a production account            | should not include a sandbox field         |
       | sandbox: false in response (explicit production)        | targets an explicit production account  | should include sandbox equals false        |
 
+  # CORRECTED to AdCP 3.1.1 enums/error-code.json: SERVICE_UNAVAILABLE is on-wire;
+  # INTERNAL_ERROR is absent from the enum (off-wire). Implementation: src/core/exceptions.py
+  # INTERNAL_CODES collapses INTERNAL_ERROR -> SERVICE_UNAVAILABLE on the wire.
   @T-UC-019-boundary-targeting-overlay @boundary @targeting_overlay @br-rule-294 @schema-v3.1
   Scenario Outline: targeting_overlay rehydration boundary - <boundary_point>
     Given the principal "buyer-001" owns media buy "mb-001" with package "pkg-001"