Use this to check if all your MCP servers are healthy. Auto-discovers servers from Claude config files, connects to each one, and verifies tools/prompts/resources respond correctly. Use with deep=true to also invoke tools and confirm they actually execute. Returns pass/fail status for every server.

Use this to test a specific MCP server before installing or after updating it. Launches the server by command, checks all capabilities, and saves a run artifact for future comparison. Example: check_server({ command: 'npx -y @modelcontextprotocol/server-everything' }). Use deep=true to invoke tools, security=true to analyze schemas for vulnerabilities.

Use this to get a quick health grade for an MCP server. Runs all checks (capabilities, tool invocation, security) and returns a 0-100 score with A-F grade and detailed breakdown across protocol compliance, schema quality, security, reliability, and performance.

Use this to find what changed between two server checks. Compares two run artifacts and surfaces regressions (things that broke), recoveries (things that got fixed), schema drift (added/removed/changed tool parameters), and gate status changes. Essential after updating a server.

Use this to retrieve the last check results for a server. Finds the most recent run artifact by target ID so you can review previous results or diff against a new run.

Use this when setting up a project or wondering what MCP servers to add. Scans the working directory for languages, frameworks, databases, and cloud providers, lists currently configured servers, and cross-references the MCP registry to recommend servers you're missing.

Use this to capture a baseline of a working MCP server. Records all JSON-RPC traffic to a cassette file that can be replayed offline (no server needed) or used to verify future versions haven't broken anything. Like VCR for MCP.

Use this to test a server without running it. Replays a previously recorded cassette offline and runs all checks against the recorded responses. Useful in CI or when the live server is unavailable.

Use this after updating a server to confirm nothing broke. Connects to the live server, sends the same requests from a recorded cassette, and compares responses. Reports exactly what changed — added tools, removed parameters, different response shapes.

Use this to check a server and see what changed since the last check. Runs all checks, saves the result, and diffs against the previous run for the same target. Shows regressions, recoveries, and schema drift in one call.

Verify that live MCP servers still match a previously saved lock file. Detects schema drift, added/removed tools, and breaking changes.

Get health score trends for MCP servers from run history.

Generate a CI regression report from run artifacts.