MCP Setup (Claude / Cursor)

probe-mcp is a stdio JSON-RPC binary bundled inside the Probe install. To use it, point your AI client at the binary’s path. No tokens, ports, or extra config — probe-mcp reads ~/.probe/api-handshake.json automatically when it starts.

Find the binary path

macOS

The binary lives inside the app bundle:

/Applications/Probe.app/Contents/MacOS/probe-mcp

If you installed Probe somewhere else, replace the prefix with that path.

Windows

The binary sits next to Probe.exe:

C:\Program Files\Probe\probe-mcp.exe

If you installed Probe per-user, look under %LOCALAPPDATA%\Programs\Probe\probe-mcp.exe.

Configure your client

Claude Code

Claude Code reads .mcp.json from your project root (or ~/.claude/mcp.json for a user-level config).

macOS

{
  "mcpServers": {
    "probe": {
      "command": "/Applications/Probe.app/Contents/MacOS/probe-mcp",
      "args": []
    }
  }
}

Windows

{
  "mcpServers": {
    "probe": {
      "command": "C:\\Program Files\\Probe\\probe-mcp.exe",
      "args": []
    }
  }
}

Claude Desktop

Edit Claude Desktop’s MCP config (Settings → Developer → Edit Config) and add:

macOS

{
  "mcpServers": {
    "probe": {
      "command": "/Applications/Probe.app/Contents/MacOS/probe-mcp",
      "args": []
    }
  }
}

The file lives at ~/Library/Application Support/Claude/claude_desktop_config.json.

Windows

{
  "mcpServers": {
    "probe": {
      "command": "C:\\Program Files\\Probe\\probe-mcp.exe",
      "args": []
    }
  }
}

The file lives at %APPDATA%\Claude\claude_desktop_config.json.

Restart Claude Desktop after saving.

Cursor

Cursor stores MCP servers in .cursor/mcp.json (project-scoped) or ~/.cursor/mcp.json (global).

macOS

{
  "mcpServers": {
    "probe": {
      "command": "/Applications/Probe.app/Contents/MacOS/probe-mcp",
      "args": []
    }
  }
}

Windows

{
  "mcpServers": {
    "probe": {
      "command": "C:\\Program Files\\Probe\\probe-mcp.exe",
      "args": []
    }
  }
}

Reload Cursor (or hit the Refresh button in MCP settings) so it spawns the new server.

Continue

Add an entry to Continue’s config.json under mcpServers:

{
  "mcpServers": [
    {
      "name": "probe",
      "command": "/Applications/Probe.app/Contents/MacOS/probe-mcp",
      "args": []
    }
  ]
}

Generic stdio client

Any MCP client that supports stdio transport works. Spawn the binary with no arguments and speak JSON-RPC 2.0 on stdin/stdout. Each request must be on a single line, terminated with \n.

/Applications/Probe.app/Contents/MacOS/probe-mcp

The first message you send should be initialize; from there, send tools/list to discover the catalog.

Verify it’s wired up

1. Make sure Probe is running. probe-mcp exits immediately with Make sure Probe is running. if it can’t read ~/.probe/api-handshake.json or the recorded PID is dead.
2. Restart your AI client so it picks up the new config.
3. Ask the AI: “What tools do you have available from probe?”
4. You should see 61 tools listed, all prefixed probe_….

If the AI says it doesn’t see any Probe tools:

• Confirm Probe is open and capturing.
• Check that ~/.probe/api-handshake.json exists (ls ~/.probe/ on macOS).
• Run probe-mcp directly from a terminal — if there’s an error, it prints to stderr.

Auth and security

You don’t pass any credentials. probe-mcp reads the bearer token straight from ~/.probe/api-handshake.json, which Probe writes with 0600 permissions on Unix (owner read/write only). Each Probe launch generates a new token; quitting Probe removes the file.

The REST API only listens on 127.0.0.1, so it’s reachable from local processes only.

Caution

If you ship a multi-user machine, treat the handshake file like an SSH key. Anyone who can read it can call the Probe API as you.

Next steps

• MCP Tool Reference — every tool, every parameter.
• Internal REST API — what’s running on the other end.
• Troubleshooting — fixes for common MCP errors.