Verification Loop Skill

Overview

Six-phase quality gate validating code changes sequentially. Each phase must pass before proceeding. Auto-detects project type and adapts commands.

When to Use

• Before committing changes
• Pre-merge validation
• CI/CD pipeline integration
• Code review preparation

Phase Definitions

Phase 1: Build

Project	Command	Skip If
Node.js	npm run build	No build script in package.json
Python	uv build / python -m build	No pyproject.toml or setup.py
Rust	cargo build --release	No Cargo.toml

Phase 2: Typecheck

Project	Command	Skip If
TypeScript	tsc --noEmit	No tsconfig.json
Python	pyright / mypy .	No type checker installed
Rust	(included in build)	Always (cargo handles types)

Phase 3: Lint

Project	Command	Skip If
JS/TS	eslint . --ext .js,.jsx,.ts,.tsx	No eslint config
Python	ruff check . / flake8 .	No linter config
Rust	cargo clippy -- -D warnings	No Cargo.toml

Phase 4: Test

Project	Command	Skip If
JS/TS	npm test / npm run test:coverage	No test script
Python	pytest --cov	No tests directory
Rust	cargo test	No tests

Phase 5: Security

Project	Command	Skip If
JS/TS	npm audit	No package-lock.json
Python	safety check / pip-audit / bandit -r .	No scanner installed
Rust	cargo audit	cargo-audit not installed

Phase 6: Diff Review

Command: git diff HEAD~1 --stat

Provides summary of changes for review context. Always informational, never fails.

Detection Logic

# Project type detection
detect_project() {
  [ -f "package.json" ] && echo "node"
  [ -f "pyproject.toml" ] || [ -f "setup.py" ] && echo "python"
  [ -f "Cargo.toml" ] && echo "rust"
}

# Skip conditions per phase
should_skip_typecheck() {
  [ ! -f "tsconfig.json" ] && [ ! -f "pyproject.toml" ]
}

should_skip_lint() {
  [ ! -f ".eslintrc.js" ] && [ ! -f ".eslintrc.json" ] && \
  [ ! -f "ruff.toml" ] && [ ! -f "Cargo.toml" ]
}

should_skip_test() {
  [ ! -d "tests" ] && [ ! -d "test" ] && \
  ! find . -name "*_test.py" -o -name "test_*.py" | grep -q .
}

Execution Flow

START -> BUILD -> TYPECHECK -> LINT -> TEST -> SECURITY -> DIFF-REVIEW -> SUCCESS
              \         \         \       \          \
               -> SKIP   -> SKIP   -> SKIP -> SKIP   -> SKIP (if conditions met)

Any phase FAIL -> STOP with error report

Configuration

Environment Variables

VERIFICATION_SKIP_PHASES="security,diff-review"  # Skip specific phases
VERIFICATION_COVERAGE_MIN=80                      # Coverage threshold
VERIFICATION_STRICT=true                          # Fail on warnings

Config File (.verification-loop.yml)

phases:
  build:
    enabled: true
    timeout: 300
  typecheck:
    enabled: true
    timeout: 120
  lint:
    enabled: true
    allow_warnings: false
  test:
    enabled: true
    coverage_threshold: 80
  security:
    enabled: true
    severity_threshold: moderate
  diff-review:
    enabled: true
    compare_ref: HEAD~1

skip_conditions:
  - pattern: "*.md"
    skip_phases: [build, typecheck, lint, test]

Error Handling

Phase	On Failure
Build	Stop, report compilation errors
Typecheck	Stop, report type errors
Lint	Stop, report lint violations
Test	Stop, report failed tests
Security	Report vulns, continue if below threshold
Diff-Review	Always succeeds (informational)

Integration

CI (GitHub Actions): Use fetch-depth: 2 for diff-review, run each phase in sequence.

Pre-Commit Hook:

#!/bin/bash
./verification-loop.sh --skip=security,diff-review
[ $? -ne 0 ] && exit 1

Metrics

Metric	Target
Pass Rate	>95%
Duration	<60s
Test Coverage	>80%

---

Version 1.0.0 (2026-01-24): Initial release