The conformance check for the MCP ecosystem

Audit any MCP server.

Paste a server URL. MCProbe lints its tool schemas, behaviorally tests them with broken inputs to catch silent failures and returns a 0–100 conformance score with the exact fixes.

2 free audits a day · no card required · $9.90 once for 30/day

example-mcp-server

fuzzed 4 of 4 tools

73C

⚠ 4 tools silently accept malformed input

Metadata10
Schema quality3.5
Error handling5.6
Liveness10
Recommended fix · Add a type so agents know what values to pass (divide.a, divide.b)

Static linters tell you a schema looks fine. MCProbe tells you the server actually behaves.

Lint the schemas

12 agent-usability rules: missing descriptions, untyped params, missing annotations and more — the things that make a tool hard for an AI to call correctly.

Fuzz the tools

It calls each tool with missing, wrong-typed and out-of-enum inputs and catches the ones that silently accept garbage instead of erroring — the failure static checks can't see.

Score & prescribe

A 0–100 conformance score across four dimensions, an A–F grade and a prioritized to-do list of exactly what to fix.

How it works

  1. 1

    Paste a URL

    Point MCProbe at any MCP server reachable over HTTP. No install, no setup on the server side.

  2. 2

    It runs the audit

    A read-only static audit by default; opt in to behavioral fuzzing to test how the server handles bad input.

  3. 3

    Get a graded report

    Score, grade, the findings and a fix list — yours to act on or to share.

Ship MCP servers agents can actually use.

Know your score before you publish — and before an agent finds the gaps for you.

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