Live MCP Client

MCP Playground

A hand-rolled JSON-RPC client against the live AINumbers MCP server at mcp.ainumbers.co. Initialize the session, list its tools, and call any tool through a generated form — every request fires only when you click a button, never on load, never on a timer. This is the one page on the site permitted to reach a network host (CONTRACT.md §A8); every other page is offline.

Clone me!
A step-by-step build of the same server: two-repo shape, the vendor-and-commit rule, the tool-name gate, the Cloudflare workarounds, and how to verify your own clone.
Read the build guide →
🔒 Every request here goes to exactly one host, https://mcp.ainumbers.co, and only when you click Send. No credentials, no PII, nothing stored — reload the page and every field, response, and log entry is gone.
How this works
Step 1 sends a JSON-RPC initialize call. Step 2 sends tools/list and renders each tool's JSON Schema as a form. Step 3 lets you fill that form and send tools/call for any one tool. Every request and response is shown raw below its section, and a copyable curl command plus an MCP client-config snippet are generated from whatever you last sent. Be gentle — the server rate-limits at 50 requests/10s per IP.
1 · initialize idle

Opens a JSON-RPC session with the MCP server and reports its declared protocol version and capabilities.

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Response 
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2 · tools/list idle

Lists every tool the server registers, with its JSON Schema input shape. Requires step 1 first.

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Response 
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3 · tools/call idle

Pick a tool from step 2's list, fill in its arguments, and call it directly against the live server.

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Response 
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Copyable snippets

Generated from the most recent request sent above. Send a request first to populate these.

  
Send a request above to generate a snippet.