name: diagnose description: "Use when the user needs failure triage, blocked-lane diagnosis, or root-cause decomposition before the next gate can move." metadata: version: "1.0.1"

Diagnose

Use this skill inside Codex when a lane is blocked, a symptom is vague, or the next useful move is to decompose the failure before editing code. diagnose is a non-gating helper skill.

Output

Produce:

• observed symptom
• likely failure slices
• missing evidence or missing reproduction steps
• smallest next probe
• exact next trigger, usually the owning lane or $maestro

Rules

• Decompose the problem before proposing broad fixes.
• Prefer the smallest reproducible boundary that can confirm or kill a hypothesis.
• Keep release-state ownership with the gated lane that is blocked.
• Escalate assumptions clearly when evidence is still incomplete.

Procedure

1. Restate the observed symptom, expected behavior, scope, and first failing boundary.
2. Build a short hypothesis tree ordered by likelihood and impact.
3. Run the smallest read-only probe that distinguishes the leading hypotheses.
4. Record exact evidence, including versions, routes, inputs, and failure output.
5. Recommend one repair owner and one verification step; do not make unrelated edits.

Quality bar

• Separate a symptom from a root cause and a contributing condition.
• Never infer success from a stale UI state, cached artifact, or unverified deployment.
• If evidence is insufficient, state the next probe instead of inventing certainty.

Example

For a plugin skill marked “Error,” inspect the archive root, manifest, skill path, front matter, and server discovery separately before changing the skill text.