Swarm

Swarm

Use a swarm for separable work. Use $arena when every worker is producing the same artifact for synthesis.

1. State the done predicate, required slices, and whether the shape is coverage, first-pass race, rank-all race, or mixed.
2. Set the worker count from the independent work and available collaboration slots. Do not create workers whose coordination cost exceeds their task.
3. Read $CODEX_HOME/pstack-models.toml when present. Default ordinary workers to general; use fast for bounded mechanical inventory and deep for hard judgment.
4. Give each worker a self-contained brief with goal, exact scope, allowed writes, verification, and report format. Separate writable files or worktrees.
5. Launch independent workers together. Wait through the Codex collaboration mechanism and avoid rapid polling.
6. Review results. Every required coverage slice needs evidence or an explicit gap. Apply the declared race rule.
7. Return one compact report with status per slice, evidenced issues, dropouts, unresolved gaps, and integrated verification.

Subagents report PASS, ISSUES, or BLOCKED with evidence. Their labels are inputs to the parent's judgment, not final authority.