fix
MUST BE USED for bug fixes that require test-first verification. Use when user says '/fix', 'fix this bug', 'fix the error', 'debug this', or provides an error/bug report. This skill mandates writing a failing test BEFORE implementing any fix, then loads the SDLC workflow.
What this skill does
# Fix (Test-First Bug Resolution)
Entry point for bug fixes that **mandates test-first verification**. Before ANY fix is implemented, the bug MUST be reproduced via automated test.
## Critical Rule: Test-First Verification
**NEVER proceed with a fix without first writing a failing test that reproduces the bug.**
This is NON-NEGOTIABLE. The workflow is:
1. **Understand** the bug report/error
2. **Write a failing test** that reproduces the issue (most concise test possible)
3. **Verify** the test fails for the right reason
4. **Then and only then** implement the fix
5. **Verify** the test passes
If you cannot reproduce the bug via automated test:
- Ask the user for more information
- Investigate further to understand the root cause
- DO NOT guess at fixes
## Why Test-First?
- **Confirms understanding**: If you can't write a test, you don't understand the bug
- **Prevents false fixes**: A test proves the fix actually works
- **Prevents regressions**: The test lives on to catch future breaks
- **Most efficient**: Avoids back-and-forth of "try this, did it work?"
## Action
**MANDATORY: Load the SDLC skill, then follow the Fix Workflow variation.**
```
Skill tool: skill="fx-dev:dev"
```
After the skill loads, execute with this modified Step 2 (Requirements Analysis):
### Modified Step 2: Bug Reproduction via Test
Before ANY implementation:
1. **Analyze the bug report** to understand expected vs actual behavior
2. **Write the most concise failing test** that reproduces the bug:
```
Agent tool:
prompt: "Load the coder skill (Skill tool: skill='fx-dev:coder'), then:
Write a FAILING test that reproduces this bug:
[BUG DESCRIPTION]
Requirements:
- Test must be as concise as possible
- Test must fail with the reported error/behavior
- Test must pass after the bug is fixed
- NO implementation yet - only the test
- Commit the failing test
Output: Test file path and failure output"
description: "Write failing bug test"
```
3. **Verify the test fails** for the expected reason
4. **Only then** proceed to Step 3 (Planning) and Step 4 (Implementation)
### Modified Step 4: Fix Implementation
When implementing the fix:
```
Agent tool:
prompt: "Load the coder skill (Skill tool: skill='fx-dev:coder'), then:
Fix this bug. The failing test is at [TEST PATH].
[PLAN FROM STEP 3]
Requirements:
- Implement the minimal fix
- The failing test must now pass
- All other tests must still pass
- Commit the fix
Output: Files changed and test results"
description: "Implement bug fix"
```
The SDLC skill provides the remaining mandatory steps (PR creation, review, CI). Follow them exactly.
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