Know when AI agents stop calling your MCP tools.
Daily checks in Claude, Cursor, ChatGPT and Codex. When your tool stops getting called, you know, and you know why.
Measured from the agent's side, not from your logs. Your server is never called.
Who calls track_order
MCP analytics · acme-shop-mcp · last 14 days · demo data
| Agent | Share of runs, 0 to 100% | Now | Why |
|---|---|---|---|
| ClaudeOpus 5.5 | 31% | CauseClaude app update | |
| ChatGPTGPT-5.5 | 34% | CauseModel update | |
| CursorSonnet 5.5 | 38% | CauseYour release v2.4 | |
| CodexGPT-5.5-Codex | 76% | Steady | |
| Gemini3.1 Pro | 77% | Steady |
You only see the calls agents make. Never the ones they skip.
No error. No log line. Your server just gets quieter.
Watch both screens: the agent looks through what it has, finds nothing, and asks the customer which shop it was. Your tool, in red, was right there.
How it works
Paste your MCP server URL.
We read its tool list and build a stand-in. Your server is never called.
Add the prompts your users type.
Every day we run them in each agent: Claude, Cursor, ChatGPT, Codex and Gemini.
See the call rate per agent.
When it drops, you get an alert with the cause (your release, the model, or the agent’s update) and a suggested fix.
Free while we build it with the first teams.
Pro from $149 a month at launch. Reserve the early-access price now; nothing to pay today.
Questions
Does Uncalled call my MCP server?
No. It reads your tool list once and builds a stand-in from it, so no test traffic ever reaches your server.
Which agents does it check?
Claude, Cursor, ChatGPT, Codex and Gemini at launch. Each one is run with the prompts your users type, every day.
What makes an agent stop calling a tool?
Three things, mostly: your own release changed the tool description or schema; a new model version weighs tools differently; or the agent app updated its built-in tools or prompts. Uncalled checks all three and names the one that matches.
How is this different from logging tool calls, like MCPcat or PostHog?
Logs show the calls that reached your server. Uncalled shows the ones that never happened, per agent, with the cause.
Who is behind it, and what does it cost?
One founder, building it with the first teams. Free during early access; Pro is planned from $149 a month at launch. Write to hello@uncalled.app.