Automated Bug & Exception Debugger

What it does

/fix is a Cursor slash command. Type it in chat to run a saved workflow: Automated Bug & Exception Debugger.

Traces runtime errors, unhandled promise rejections, and failing test suites back to their root cause and generates clean, minimal bug fixes.

Analyzes stack traces and failing tests to pinpoint and resolve root causes. Unlike a skill, a command is something you invoke on purpose. The agent does not decide to run /fix for you.

Why it exists

Founders retype the same multi-step prompt until it rots. /fix exists so the pipeline, all 4 steps of it, is a file in .cursor/commands, versioned with the repo.

It ships in the Engineering Kit. It is wired to the Root Cause Debugger (debugger) and Test Automation Engineer (test-automator) agents. Required skills: Resilient Error Handling & Fault Tolerance; Vitest Unit & Integration Testing; Strict TypeScript Standards & Type Safety.

When to use it

• Use when encountering runtime exceptions, hydration errors, or failing test suites.
• Use /fix when you want that pipeline, not a freeform chat. If you only need one step, use a narrower command or a single agent.
• Start a new chat. Do not run this command in a thread that just wrote marketing copy.

When not to use it

• Do not run /fix as a substitute for reading the diff. The command produces files; you still gate them.
• Do not chain it into a 40-turn chat. Fresh context is part of the design.
• Do not run it if you have not filled CURSOR.md. The pipeline will invent a stack.

Example workflow

1. Parse error stack trace and locate exact source file line numbers
2. Isolate reproducing conditions and write a minimal failing test
3. Apply surgical bug fix without modifying unrelated code logic
4. Run test suite to verify the error is resolved without regressions

Example usage

Type this in Cursor chat: /fix Resolve null pointer exception in user session hydration loop

The command file tells the session which agents to adopt and which skills to read. You should see phase headers, not a single dump of code.

If a phase fails its gate, stop. Do not add 'just continue'.

Example output

• Expected artifact: Relevant modified source files
• Expected artifact: tests/...

Best practices

• Keep the prompt specific. /fix Resolve null pointer exception in user session hydration loop is the shape: object, constraint, and outcome.
• Let the listed agents work in order: debugger → test-automator.
• Save outputs in the repo. Chat-only answers evaporate.
• Engineering commands should leave tests or an audit note, not only implementation files.

Common mistakes

• Typing /fix with no object ('do the thing'). The pipeline will guess.
• Re-running the command in the same chat after a failed gate instead of fixing the failing file.
• Editing the command file to skip review so it 'goes faster'.
• Skipping the Resilient Error Handling & Fault Tolerance skill that the command depends on.