diagnose-loop

name	diagnose-loop
description	Debug failures systematically.

Diagnose Loop

Purpose

Debug failures systematically.

When to use

Use when a command fails, behavior is wrong, a test regresses, or output does not match the spec.

Inputs

• Failure report
• Exact command or reproduction case
• Recent changes
• Logs, traces, or output

Workflow

1. Freeze feature work.
2. Reproduce the failure.
3. Identify the exact failing command or case.
4. List hypotheses.
5. Instrument minimally.
6. Apply the smallest fix.
7. Add a regression check if possible.
8. Rerun the original failing command.
9. Rerun relevant verification.

Outputs

• Root-cause note
• Smallest fix
• Regression check when possible
• Rerun results

Stop conditions

• The original failure is fixed and verified.
• The failure cannot be reproduced.
• The next step requires a product or data decision.

Anti-patterns

• Randomly editing files before reproducing the bug.
• Fixing symptoms without naming the failing case.
• Adding noisy instrumentation and leaving it behind.