Interactive MCP Playground & Console

Test Model Context Protocol (MCP) servers live in your browser. Inspect protocol handshakes, send tools/call requests, and validate JSON-RPC 2.0 responses.

Outgoing Request (JSON-RPC 2.0)

{
  "jsonrpc": "2.0",
  "id": 3,
  "method": "tools/call",
  "params": {
    "name": "search_mcp_servers",
    "arguments": {
      "query": "postgres",
      "limit": 5
    }
  }
}

Server Response Inspector

// Click "Send JSON-RPC Request" to execute against the endpoint

How the MCP Playground Works

The playground sends JSON-RPC 2.0 requests straight from your browser to an MCP endpoint over HTTP and shows the raw response. It points at the AllMCPs MCP server by default, so you can try tools/list and tools/call without installing anything and see exactly what a client exchanges with a server.

To test your own remote server, change the endpoint URL. The server must accept cross-origin requests from the browser (CORS), and servers that require an initialize handshake, a session ID, or OAuth will reject bare requests — use the protocol inspector to decode those responses, or the official MCP Inspector for a full session.

Frequently Asked Questions (FAQ)

A browser console for sending Model Context Protocol requests such as tools/list and tools/call to a server and reading the JSON-RPC responses. It is useful for learning the protocol and checking what a remote server returns.