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Brandon
Brandon

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Stop asking AI what this error means — ask it to find the root cause instead

When I paste an error into Claude without a slash command, I get an explanation of the error message I already read.

When I use this command, I get the reason three stack frames up that caused the problem in the first place.

The command

Create .claude/commands/debug-trace.md:

I will paste a stack trace. Find the root cause — not the symptom. Trace back through the call stack to the point where something first went wrong, not just where it crashed. Explain: what the error means, why it happened (the real reason, not "null is not an object"), what state the application was in when it occurred, and the one-line fix. If you need to see specific files, ask for them.
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The difference in practice

Without this command: "TypeError: Cannot read properties of undefined — this occurs when you try to access a property on an undefined value."

Thanks, I can read.

With /debug-trace: "The error occurs in UserProfile.tsx at line 47, but the root cause is in useAuth.ts line 23 — the token is undefined because getToken() is called before the auth state has initialized. The fix is to add a loading guard..."

The instruction "not the symptom" is load-bearing. Without it, you get an explanation of the error message. With it, you get the actual cause.

How to set up slash commands

Create .claude/commands/debug-trace.md with the prompt above as the file content. Run /debug-trace in a Claude Code session, then paste your stack trace.

The command has access to your full project — it can read the files involved in the error without you copying them manually.

Real stack trace example

Paste any Node.js, React, Python, or Java stack trace after typing /debug-trace. Claude reads your project files to trace the call chain and finds where state went wrong.


If you have a specific type of error this does not handle well — async errors, database errors, test failures — drop it in the comments.

Full kit (75 commands + 10 CLAUDE.md templates + 8 hooks): Claude Code Power User Kit

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