fix(adk): re-send task_id/agent_id in state updates for backend compatibility

[max-parke-scale]

What

StateService.update_state re-sends task_id/agent_id in the states.update request body (via extra_body).

Why

0.13.0's Stainless-generated client dropped task_id/agent_id from states.update(), and the ADK stopped sending them. Backends predating scale-agentex#278 still require those fields, so every state write returned 422 Field required. On the Cengage agent (centipede-student-assistant-agentex-agent) this dropped multi-turn context on every turn — ~22k failures over ~21h, logged at warn level so nothing alerted.

Backends post-#278 accept-and-ignore the fields, so re-sending is compatible with both old and new servers — it closes the version-skew window where the client outran the backend rollout reaching the customer (2.10.0-rc).

Test

tests/lib/adk/test_state_service.py asserts update_state forwards task_id/agent_id in the request body — KeyErrors without the fix. ruff check, pyright, and the test pass locally.

Notes

Issue #1 of 3 from the 0.13.0 incident; ships in the 0.13.1 hotfix. The namespace-version guard (issue #2) is a separate PR; the APM route-doubling (issue #3) is under investigation.

🧑‍💻🤖 — posted via Claude Code

Greptile Summary

• Restores ADK state update compatibility by sending task_id and agent_id in the states.update request body via extra_body.
• Keeps the generated state parameter while adding the legacy identifiers required by older backends.
• Adds regression coverage for forwarding the parent identifiers during StateService.update_state.

Confidence Score: 5/5

The change is narrowly scoped to restoring compatibility for ADK state updates and includes targeted regression coverage.

No correctness issues were identified in the changed service logic or test coverage, and the update preserves the generated state payload while adding the legacy identifiers expected by older backends.

T-Rex Logs

What T-Rex did

• Observed the pre-change state-update test output, which exited with code 0 and showed mocked states.update kwargs without extra_body.
• Observed the post-change state-update test output, which exited with code 0 and showed mocked states.update kwargs now including extra_body with {'agent_id': 'a1', 'task_id': 't1'}, while state_id and state remained unchanged (state_id: 's1', state: {'k': 'v'}).
• Reviewed the regression-test attempt log, which documented the command and import blocker and did not contradict the direct head behavior shown by the before/after results.

_{Ran code and verified through T-Rex}

_{Reviews (1): Last reviewed commit: "fix(adk): re-send task_id/agent_id in st..." | Re-trigger Greptile}