Start passive. Escalate with intent.

mcp-doctor separates what can be learned without calling a tool from diagnostics that require exact authority and reviewed cases.

Inspect a server without calling tools

Put a local server command after --, or pass a remote Streamable HTTP endpoint. Inspection validates discovery, definitions, schemas, protocol behavior, runtime limits, and cleanup without invoking a tool.

Local STDIO server

mcp-doctor inspect -- node ./dist/server.js --stdio

Remote Streamable HTTP server

mcp-doctor inspect https://mcp.example.com/mcp

Connection is only the first check

A server that initializes can still expose unusable guidance, invalid schemas, broken results, or unsafe lifecycle behavior.

Use reviewed scenarios for active behavior

When passive evidence is not enough, use one exact tool and a reviewed scenario that declares its effect classification. Do not grant broad, implied authority to generated inputs.

Reviewed check scenarios Read the authoritative scenario format, authorization gates, and execution semantics.

What diagnostics can cover

Protocol and JSON-RPC failures
Tool guidance and input schemas
Result-contract validation
Timeouts, crashes, output limits, and cleanup
Repeatable active scenarios and edge cases
Deterministic automation artifacts