[bokelley]

Summary

Backports #3280 to the 15.9.x maintenance line so it ships as @adcp/sdk@15.9.2 on npm latest. SDK 16 is beta-only, and adcontextprotocol/adcp depends on 15.8.1.

• Capability discovery validates get_adcp_capabilities against the caller's pin instead of the served adcp_version #3278: discoverAgentProfile and TaskExecutor validate get_adcp_capabilities against the seller's echoed adcp_version instead of the caller's pin.
  • The echo is used only when it is a release-precision value in the pin's major that the SDK bundles a schema for. Otherwise the pin is used.
  • An external schemaRoot bound to the pin still wins.
  • Validation stays strict.
  • This fixes false capabilities_schema_issues for 3.0-pinned probes of 3.1+/3.2 sellers. A 3.0 pin negotiates major-only, so the seller serves its highest 3.x release (versioning spec, "Server echoes").
• Capability cross-check keys comply_test_controller as 'compliance' instead of 'compliance_testing', failing every compliance-capable agent #3279: the testCapabilityDiscovery cross-check keys comply_test_controller under compliance_testing, not compliance. The table keys are type-checked against AdcpProtocol.

Backport notes

• The three commits from fix(testing): validate capabilities against the served release; key compliance_testing in the cross-check #3280 cherry-pick cleanly. The touched code (testing/client.ts, core/TaskExecutor.ts, testing/scenarios/capabilities.ts, validation/schema-loader.ts) is identical on 15.9.x apart from line offsets.
• The helper lives in schema-loader.ts rather than a new module. That keeps the client/core eager graph and the packed file count inside their budgets.
• No release plumbing changes. 15.9.x's release.yml already publishes stable 15.9.x patches to latest.
• Both changesets are patch for @adcp/sdk.

Test plan

• test/lib/capabilities-served-release-validation.test.js (17 tests) passes on 15.9.x.
• npm test locally. Every non-Postgres suite passes, including the eslint-plugin and reference-renderers workspaces. The only failures are Postgres-backed tests (ECONNREFUSED, no local database), the same set as on main. CI's Postgres-backed unit tests are green.
• typecheck, lint (0 errors), format:check, verify:package, check:package-size (6565 files)

Fixes #3278 and #3279 on the 15.x line.

🤖 Generated with Claude Code

[aao-secretariat]

Ladon verdict: Approve

Approve.

Two correct, well-tested bug fixes with no findings at Medium or above.

1. src/lib/testing/scenarios/capabilities.ts:321 — re-keys the cross-check map compliance→compliance_testing to match parseCapabilitiesResponse output and the COMPLIANCE_TOOLS→compliance_testing TOOL_PROTOCOL_MAP entry; type-checked via satisfies Partial<Record<AdcpProtocol,...>>.
2. src/lib/validation/schema-loader.ts:1258 — resolveServedValidationVersion selects the seller's echoed release per the versioning spec, failing closed to the pin on every ambiguous case and regex-gated against path traversal. Strict validation preserved, not loosened. No witness-not-translator concern: only the schema-version selector changes; no data fabricated or reshaped.

Changesets present and correctly typed patch for bug fixes; no public export removed/renamed. No new external I/O or timeout surface. Test coverage sound (major-only envelope + external-schema-root precedence cases; reuses established MCP scaffolding pattern).

No high-risk flag, no gated paths, no author team gate, no prior decision. Decision table falls through rows 1–8 to row 9.