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