Phase 3 — Delegate

Match the executor to the task, not the other way around. The point is cost and speed without losing quality — the coordinator stays accountable for the result.

Executor matrix

Tier definitions and per-vendor model examples: model-tiers.md.

Task profile	Executor
Trivial: mechanical edit, config tweak, typo, doc update	Do it directly, or batch on a trivial-tier model
Standard, well-specified implementation	Coordinator itself, or a same-tier subagent for parallelism
Hits an escalation trigger (see escalate.md)	Escalation-tier subagent, for that one specific question

• The coordinator typically runs at implementer tier itself, so standard tasks are usually executed directly rather than delegated. Delegate anyway when there's real parallelism — independent tasks, each in its own worktree — or to shed trivial mechanical work onto a cheaper model.
• Escalation is never the default path for "ambiguous" or "architectural" — it fires only on the concrete triggers in escalate.md, and only for the specific question, not the whole task.

What a delegation carries

Hand the subagent its full pinned spec from Phase 2, plus:

• The verification commands it must run and pass before reporting done.
• The instruction to report what it changed and what it verified — not just "done".
• The instruction to stop and report when it hits something the spec does not cover, instead of improvising scope.

What is never delegated downward

Analysis, final verification, and delivery never go to an implementer — they stay with the coordinator or go up to Escalation tier for a specific question:

• Analysis and root-cause work (Phase 1).
• Final verification (Phase 5) — an implementer's green run is a claim, not a result.
• Commits, history rewrites, pushes, and user-facing reporting (Phase 6) — these stay with the coordinator regardless of tier; they're about accountability, not capability, so they never go to Escalation tier either.