README.md
Deterministic, network-free, read-only MCP guardian for Python license headers
mcp-license-header-guardian
Deterministic, network-free, read-only MCP guardian that enforces license headers in tracked Python files (Tier 1).
What this repo is for
Use this repository as the starting point for new guardians.
It provides:
- A frozen V1 contract (
docs/V1_CONTRACT.md) - Canonical output examples (
docs/EXAMPLE_OUTPUTS.md) - Determinism guardrails (pytest)
Invariants (do not violate under V1)
- One tool only:
check_license_header - Output schema keys are fixed
- Fail-closed on invalid input or internal error
- No timestamps, randomness, environment metadata
- No network calls
- No repo mutation / disk writes
If you need any of the above, declare V2.
Local development
Install editable:
python3 -m pip install -e .
Run tests:
pytest -q
Print canonical JSON output:
python3 -c "from mcp_license_header_guardian.server import check_license_header, canonical_json; print(canonical_json(check_license_header('.')))"
MCP server
Run:
mcp-license-header-guardian
Tools (1)
check_license_headerVerifies the presence and correctness of license headers in Python files.Configuration
claude_desktop_config.json
{"mcpServers": {"license-header-guardian": {"command": "mcp-license-header-guardian"}}}Try it
→Check the license headers for all Python files in the current directory.
→Verify if the license header in my project files complies with the standard.
→Run a license header audit on the repository using the guardian tool.