| created | "2026-02-22T00:00:00.000Z" |
| modified | "2026-06-18T00:00:00.000Z" |
| reviewed | "2026-06-10T00:00:00.000Z" |
| description | Derive test regression plans from git history by finding commits lacking tests. Use when finding untested bug fixes, coverage gaps, or generating a test backlog. |
| args | [--since DATE] [--quick] [--scope AREA] |
| argument-hint | --since 2024-06-01 for date range, --quick for last 50, --scope auth for specific area |
| allowed-tools | Read, Write, Glob, Grep, Bash, AskUserQuestion, Task |
| model | opus |
| name | blueprint-derive-tests |
/blueprint:derive-tests
Analyze git history to identify fix and feature commits lacking corresponding test changes, then generate a structured Test Regression Plan (TRP) document as a prioritized test backlog.
Use case: Systematically close test coverage gaps by mining commit history for bug fixes and features that shipped without regression tests.
When to Use This Skill
| Use this skill when... | Use alternative when... |
|---|
| Bug fixes ship without regression tests | You need to run existing tests (/test:run) |
| Want a prioritized test backlog from history | Writing tests for a specific feature (manual TDD) |
| Onboarding a project and assessing test health | Checking current test coverage metrics |
| Need to find which fixes lack test coverage | Designing a test strategy from scratch (/test:architecture) |
Context
- Git repository: !
git rev-parse --git-dir
- Blueprint initialized: !
find . -path '*/docs/blueprint/*' -maxdepth 3 -name 'manifest.json' -type f
- Total commits: !
git rev-list --count HEAD
- Test framework: !
find . -maxdepth 3 \( -name 'vitest.config.*' -o -name 'jest.config.*' -o -name 'pytest.ini' -o -name 'pyproject.toml' -o -name 'Cargo.toml' -o -name 'go.mod' \) -type f -print -quit
- Test files: !
find . -maxdepth 4 -type f \( -name '*.test.*' -o -name '*.spec.*' -o -name 'test_*' -o -name '*_test.*' \) -print
- Conventional commits sample: !
git log --format="%s" --max-count=10
Parameters
Parse these from $ARGUMENTS:
--quick: Fast scan (last 50 commits only)--since DATE: Analyze commits from specific date (e.g., --since 2024-06-01)--scope AREA: Filter to commits touching a specific area/scope (e.g., --scope auth)
Default behavior without flags: Analyze last 200 commits.
For detailed templates, severity matrix, and test mapping rules, see REFERENCE.md.
Execution
Execute this test regression plan derivation workflow:
Step 1: Verify prerequisites
