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MCP Checker

Free10-second check

Quick MCP server health check. Paste any MCP server URL — the checker runs the initialize handshake, confirms capabilities are advertised, and lists every tool, prompt and resource the server exposes. No install, no sign-up.

Server is up — now what?

Drive your verified server with Claude, GPT or Gemini and watch real tool calls in a live conversation.

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✦ Free credits on sign-up · no credit card

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What does the MCP checker actually check?

The MCP checker is a quick health-check tool. It connects to the URL you paste, runs the MCP initialize handshake, and verifies the basics: the server is reachable, the protocol version is current, capabilities are advertised, and the standard tools/list, prompts/list and resources/list endpoints respond.

Think of it as curl for MCP — paste the URL, see if the server is alive, and inspect what it offers. If anything is broken, the JSON-RPC log shows you the exact error code and message.

Checks the checker runs

  • Connectivity — the URL responds and accepts an MCP connection
  • Protocol handshake — initialize succeeds and returns server info
  • Protocol version — matches a version this client supports
  • Capabilities — tools, prompts and resources flags are advertised correctly
  • tools/list — server returns at least one tool with a valid schema
  • Auth behavior — surface 401 / 403 if the server is protected
  • Transport — confirms whether HTTP + SSE or Streamable HTTP is in use

When you would use the MCP checker

  • After a deploy — confirm your remote MCP server is reachable and serving the new tool list
  • Debugging Claude Desktop — Claude says "no tools" — is the server actually exposing any?
  • Picking a public server — verify a server from the directory still works before wiring it up
  • Onboarding a teammate — share the checker URL so they can sanity-check the server you built
  • CI smoke tests — copy the JSON-RPC export and pin it as a baseline

Beyond a basic check — also check security

The checker confirms your server works. The MCP security scanner confirms it is safe to expose. A February 2026 sweep found over 8,000 MCP servers on the public internet with no authentication — many of which would have looked healthy in a checker like this one.

Run both: checker for "is it up?", security scanner for "is it safe?".

Frequently Asked Questions

How long does an MCP check take?
Usually under 10 seconds. The checker opens one connection, runs the initialize handshake and then lists tools/prompts/resources in parallel. For slow servers it will wait, and the JSON-RPC log shows you exactly where the latency is.
My MCP server returns "no tools" — what's wrong?
Most common causes: the server didn't advertise the tools capability in initialize; tools/list returns an empty array; or your token doesn't have permission to see them. The checker surfaces all three in the log — paste the export into a GitHub issue if you need help.
Can I check an MCP server that needs a Bearer token?
Yes. Paste the token in the auth field; the checker sends it on every request. A 401 or 403 in the log means the server is enforcing auth — which is the answer you usually want.
Does the checker work with local STDIO servers?
No — STDIO servers need a local child process, which browsers can't spawn. Use npx @modelcontextprotocol/inspector for STDIO, and this online checker for any remote (HTTP / SSE / Streamable HTTP) server.
Is the MCP checker free?
Yes, completely. No sign-up, no rate limit on the checker, no credit card.

Related tools

MCP Checker — Quick Health Check for Any MCP Server URL (Free) | MCP Playground