Release 0.12.5

[github-actions]

Release readiness review (v0.12.4 -> TARGET 978ab84)

This is a release readiness report done by $final-release-review skill.

Diff

v0.12.4...978ab84

Release call:

🟢 GREEN LIGHT TO SHIP patch release contains targeted bug fixes and additive MCP transport params with matching test coverage and no confirmed blocking issues.

Scope summary:

• 10 files changed (+680/-41); key areas touched: src/agents/agent.py, src/agents/mcp/server.py, src/agents/items.py, src/agents/run_internal/turn_resolution.py, MCP/runtime tests, and version bump in pyproject.toml/uv.lock.
• Commit sequence reviewed (oldest->newest): retry ClosedResourceError, expose auth/httpx_client_factory, retry MCP 408 in isolated session, streaming nested-agent output recovery, version bump to 0.12.5.

Risk assessment (ordered by impact):

No material risks identified.

Notes:

• Base tag was selected from local tags only, per request: v0.12.4.
• Working tree was clean during review.
• Local verification was not rerun in this review; assessment is based on concrete diff and added/updated tests in the release range.