12. Debugging and incident postmortems

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The two Skills answer different questions.

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12. Debugging and incident postmortems

When to use this flow

The two Skills answer different questions. Choose based on where you are in the incident.

What you want to doQuestionSkill to use
You can't figure out why a bug keeps happening"What is actually causing this to fail?"ywc-debug-rootcause
A Production incident already happened and you need a written record"What do we tell the team (and customers)?"ywc-incident-postmortem

ywc-debug-rootcause - Root-cause investigation

claude code
ywc-debug-rootcause The payment webhook is sometimes processed twice. I can't find the cause

This prevents patches that only address symptoms and forces a four-step root-cause investigation. If fixes fail at the same point three or more times, it guides you to question the architecture itself.

ywc-incident-postmortem - Postmortem authoring

claude code
ywc-incident-postmortem --client

--client additionally creates a customer-facing summary that omits internal details.

How the two connect

ywc-debug-rootcause runs while the incident is still live and answers why it happened. ywc-incident-postmortem runs after the fix has shipped and turns that root cause into a timeline, impact assessment, and prevention action items — it can take a root-cause verdict as one input to its own analysis rather than repeating the investigation from scratch. Use them in that order: find the cause first, then write it up.


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