Local activation results were derived only from committed Session events.
When the first turn/end append failed, no ending existed and the result
defaulted to completed. When the first turn/start append failed, the initial
message remained unclaimed and kept the idle activation resident forever.
Both paths emitted agent/error but had no durable terminal to project.
Retain the log offset of the latest exact-Agent live failure on the local
activation. Clear it only when the same Session commits a turn/end at or
after that offset, so a later recovery can supply its own outcome and a
reentrant older terminal notification cannot erase a newer failure. The
child scope owns both observers and removes them with its Agent handle.
Capture error while that live failure remains. Let the failed local
activation settle despite its own unclaimed inbox, while preserving the
existing requirement to wait for owned descendants. Wake its settlement
observer when a live failure changes readiness. No public API, raw Agent
idle semantics, or descendant teardown policy changes.
Add regressions through real local activation creation for first start/end
append failures, recovery by later durable endings, exact-Agent isolation,
and an error emitted reentrantly during an older terminal notification.
Update the bilingual package contract and generated event consumer graph.
Validation:
- Both first-append regressions reproduced before the fix: turn/start
remained pending; turn/end returned completed instead of error.
- Six focused behavior cases passed after the fix.
- 423 subagent package tests passed; activation.ts and manager.ts reached
100% statements, branches, functions, and lines under scoped coverage.
- pnpm exec tsc -b packages/subagent/subagent/tsconfig.json passed.
- Focused source/test oxlint and git diff --check passed.
- doc-sync passed 41 gates; its sole stale event-graph failure was corrected
with gen-doc-graphs, then verify-doc-graphs passed for all seven graphs.
- README translation pairing regenerated and passed the doc-sync check.
Tianyi Cui
1dbbc59d3e