delegating-subagentslisted

# Delegating to Subagents A subagent's return value is not a delivery channel. Treat it as a courtesy. The artifact the agent writes to disk is the delivery channel. ## The rule 1. **Every brief names an output file.** Absolute path, stated in the prompt. 2. **The orchestrator reads that file** the moment the agent finishes, goes idle, or is given up on. Unconditionally, before drawing any conclusion. 3. **A missing file is a distinct outcome** from an agent that found nothing. Say which one happened. ## Why, with numbers Measured across 22 delegations in one session on 2026-08-16 and 17: | Spawn mechanism | Returned a result inline | |---|---| | Skill tool with `context: fork` and an `agent:` in frontmatter | 11 of 11 | | Agent tool, any `subagent_type`, plugin or built-in | 0 of 11 | The Agent-tool spawns were not hung and not idle. Four of them wrote code, ran their tests and committed. Two wrote full reports to the paths their briefs named. The only signal that came back was an idle notification carrying no payload. The cost of ignoring this: two blocking defects sat in a written report for a day while the orchestrator rediscovered them by hand, and a third finding in another report was never seen at all. The reports were on disk the whole time. ## What does not work - Waiting longer. The result is not in flight; there is nothing to wait for. - `SendMessage` asking for the result. Sometimes recovers it, often does not. Three escalating rounds, including