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