Codex Adversarial Gate

Use this skill to prevent Codex from marking implementation work complete just because the implementing thread is confident.

Default to implementation closeout for implementation work. Plan review still exists for drafting or updating plans, but routine implementation should spend budget on completion review and archival, not on re-litigating an accepted plan.

When this skill is active, it is a phase/slice-boundary gate, not a final closeout add-on. Loading the skill, keeping a pending reminder, or saying the gate will happen later does not count as using it. Each reviewable phase, slice, checkpoint, or grouped implementation unit must stop at its completion boundary until the completion reviewer and critic outputs are archived.

Routing

Use the bundled custom agents when installed:

• plan_adversarial_reviewer: plan drafting, plan updates, and plan finalization only.
• task_completion_adversarial_reviewer: implementation phase/slice closeout only.
• task_completion_review_critic: audit any completion-review PASS before the implementer accepts it.

If the environment supports separate reviewer contexts but not these custom agents, use the prompts in references/reviewer-prompts.md with equivalent read-only reviewer contexts. If no independent reviewer context is available, do not self-review; stop with BLOCKED_REVIEW_CONTEXT_UNAVAILABLE and ask the user for a separate review path.

Never use plan_adversarial_reviewer to close implementation work. A phase/slice is complete only after task_completion_adversarial_reviewer returns a preliminary PASS, task_completion_review_critic returns AGREE_PASS, and both review records are archived in the repo.