A spawn whose goal (NFKC, case, whitespace and punctuation folded) matches a
child of the same parent that is still queued/running, or succeeded/waiting
within the last 10 minutes, returns that child instead of creating a new one:
output gets reused=true, a message ("已有同目标子会话…") and the child's
current result summary. Failed/cancelled/over-budget children are not reused.
Spawn decisions are serialized per parent in-process so parallel duplicate
calls in one batch create a single child. Replays keyed by idempotency still
hit the original child as before. The subagent constraint in the system prompt
asks for Chinese sub-goals and no duplicate spawns.
Co-Authored-By: Claude Opus 5.5 <[email protected]>
