Fixes broken test suites by identifying patterns and applying targeted code updates.

Install

mkdir -p .claude/skills/test-fixing && curl -L -o skill.zip "https://agentskills.codes/api/skills/download/2555" && unzip -o skill.zip -d .claude/skills/test-fixing && rm skill.zip

Installs to .claude/skills/test-fixing

Activation

This is the description your AI agent reads to decide when to run this skill — the better it matches your request, the more reliably it fires.

Run tests and systematically fix all failing tests using smart error grouping. Use when user asks to fix failing tests, mentions test failures, runs test suite and failures occur, or requests to make tests pass.
211 chars✓ has a “when” trigger
Intermediate

Key capabilities

  • Identify failing tests via make test
  • Group failures by error type or module
  • Prioritize fixes based on impact and dependency
  • Verify fixes using focused test execution
  • Perform final regression testing

How it works

It systematically groups test failures by error type or module, then applies fixes in a specific order starting with infrastructure, followed by API changes, and finally logic issues.

Inputs & outputs

You give it
Failing test suite output
You get back
Passing test suite and resolved code

When to use test-fixing

  • Fix failing test suite
  • Debug broken CI/CD pipelines
  • Resolve test regressions after refactoring

About this skill

Test Fixing

Systematically identify and fix all failing tests using smart grouping strategies.

When to Use

  • Explicitly asks to fix tests ("fix these tests", "make tests pass")
  • Reports test failures ("tests are failing", "test suite is broken")
  • Completes implementation and wants tests passing
  • Mentions CI/CD failures due to tests

Systematic Approach

1. Initial Test Run

Run make test to identify all failing tests.

Analyze output for:

  • Total number of failures
  • Error types and patterns
  • Affected modules/files

2. Smart Error Grouping

Group similar failures by:

  • Error type: ImportError, AttributeError, AssertionError, etc.
  • Module/file: Same file causing multiple test failures
  • Root cause: Missing dependencies, API changes, refactoring impacts

Prioritize groups by:

  • Number of affected tests (highest impact first)
  • Dependency order (fix infrastructure before functionality)

3. Systematic Fixing Process

For each group (starting with highest impact):

  1. Identify root cause

    • Read relevant code
    • Check recent changes with git diff
    • Understand the error pattern
  2. Implement fix

    • Use Edit tool for code changes
    • Follow project conventions (see CLAUDE.md)
    • Make minimal, focused changes
  3. Verify fix

    • Run subset of tests for this group
    • Use pytest markers or file patterns:
      uv run pytest tests/path/to/test_file.py -v
      uv run pytest -k "pattern" -v
      
    • Ensure group passes before moving on
  4. Move to next group

4. Fix Order Strategy

Infrastructure first:

  • Import errors
  • Missing dependencies
  • Configuration issues

Then API changes:

  • Function signature changes
  • Module reorganization
  • Renamed variables/functions

Finally, logic issues:

  • Assertion failures
  • Business logic bugs
  • Edge case handling

5. Final Verification

After all groups fixed:

  • Run complete test suite: make test
  • Verify no regressions
  • Check test coverage remains intact

Best Practices

  • Fix one group at a time
  • Run focused tests after each fix
  • Use git diff to understand recent changes
  • Look for patterns in failures
  • Don't move to next group until current passes
  • Keep changes minimal and focused

Example Workflow

User: "The tests are failing after my refactor"

  1. Run make test → 15 failures identified
  2. Group errors:
    • 8 ImportErrors (module renamed)
    • 5 AttributeErrors (function signature changed)
    • 2 AssertionErrors (logic bugs)
  3. Fix ImportErrors first → Run subset → Verify
  4. Fix AttributeErrors → Run subset → Verify
  5. Fix AssertionErrors → Run subset → Verify
  6. Run full suite → All pass ✓

When not to use it

  • Non-test related code debugging
  • Fixing issues without existing test coverage

Prerequisites

makepytestuv

Limitations

  • Requires existing test suite
  • Fixes must follow project conventions

How it compares

It uses a structured grouping strategy to resolve root causes rather than addressing individual test failures in isolation.

Compared to similar skills

test-fixing side by side with the closest alternatives in the catalog.

SkillInstallsUpdatedSafetyDifficulty
test-fixing (this skill)19moReviewIntermediate
python-testing-patterns772moReviewIntermediate
fix-bug117moReviewIntermediate
fixing-bugs-systematically18moNo flagsIntermediate

Try saying

Example prompts that trigger this skill in your AI assistant.

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