Trust MCP Server

MCP Trust Registry

Check before you connect. A neutral, public danger grade for the MCP servers your AI agents rely on.

Live: mcp-trust.vercel.app

Not yet published to PyPI. Install from source using the Quickstart below.

Use as an MCP server

mcp-trust runs as a read-only MCP server so an agent can check a server's danger grade before connecting — it serves a baked snapshot of real, sandboxed grades, so no database or network is needed.

mcp-trust mcp-serve          # from a source/dev install (works today)
uvx mcp-trust mcp-serve      # once published to PyPI

Connecting an MCP server hands it influence over what your agent does. Tool poisoning, prompt injection, over-broad permissions, and rug-pull tool mutations are documented attack classes -- and today there's no quick way to vet a server before you wire it in. MCP Trust Registry scans public MCP servers and gives each one a single readable danger grade (A-F), a separate transparency signal, and the findings behind them.

Think OSV.dev / Socket.dev / haveibeenpwned, scoped to MCP servers.

Prerequisites

• Python >= 3.11
• uv (used for dependency management and running the project)

How it works

register a server  ->  scan via engine  ->  derive grade  ->  persist  ->  serve at a stable URL

The registry does not reimplement vulnerability detection. It orchestrates a pluggable scan engine -- the shipping backend wraps the public mcp-audits (>=2.1) package -- and owns the catalog, the public trust-grade normalization, persistence, and the lookup API.

Quickstart

git clone https://github.com/saagpatel/mcp-trust.git && cd mcp-trust
uv pip install -e ".[dev]"      # core + dev deps (runs on the built-in StubEngine)
mcp-trust seed                  # load the seed catalog
mcp-trust scan mcp-reference-time   # scan a catalog server, print its grade
mcp-trust check mcp-reference-time  # look up the latest stored grade
mcp-trust serve                 # serve the API on http://127.0.0.1:8000

For real scanning install the engine extra and select it:

uv pip install -e ".[dev,engine]"
MCP_TRUST_ENGINE=mcpaudit mcp-trust scan mcp-reference-time

Scanning launches the server's process. For untrusted servers, isolate execution in a locked-down container (no network, read-only fs, dropped caps, resource limits):

MCP_TRUST_ENGINE=mcpaudit MCP_TRUST_SANDBOX=docker mcp-trust scan mcp-reference-time

The default is no sandbox (safe only for servers you trust).

API

Every server has two orthogonal signals: a danger grade (A-F) and a transparency level (high/medium/low, from annotation coverage). Automated grades are not endorsements, certifications, or claims that a server is malicious. A low grade on a low-transparency server means "cannot verify safe," not "known dangerous."

HTTP scan triggering is fail-closed by default. Public deployments should set MCP_TRUST_PUBLIC_READONLY=1, which makes POST /servers/{slug}/scan return 403 before any engine can run. Operator scans should normally run through the CLI against the persistent registry DB, not through public traffic.

For local API demos with the deterministic StubEngine, set MCP_TRUST_ALLOW_UNAUTHENTICATED_STUB_SCANS=1. Do not set that in public. Token-gated API scan triggering is still available for private operator surfaces by setting MCP_TRUST_SCAN_TOKEN and passing it as Authorization: Bearer <token> or X-MCP-Trust-Scan-Token.

Set MCP_TRUST_RECEIPTS_DIR=/data/mcp-trust/receipts during real scan runs to archive a JSON receipt for each scan and store its portable artifact filename in report_ref.

Status

Live at mcp-trust.vercel.app as a statically generated catalog, regenerated from the local registry. The seven official reference MCP servers carry real mcp-audits grades from network-off Docker sandbox scans (distribution A/B/B/C/D/F/F). Every grade is labeled by provenance, so demo/stub data can never read as a real scan, and an unscanned server never shows a letter grade.

The static front door is the low-ops launch path (see DEPLOY-VERCEL.md); a weekly launchd job under deploy/launchd/ re-scans, rebuilds, and optionally redeploys (deploy is opt-in). The live FastAPI service + VM path remains documented in DEPLOY-VM.md as an alternative. See SPEC.md for the full contract and LAUNCH-GATE.md for launch history.

Contributing

uv.lock is intentionally committed to the repository to ensure reproducible installs across environments. When adding or updating dependencies, commit the updated uv.lock alongside your pyproject.toml changes.

License

MIT