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ToolFit MCP Server Preflight Checker
x402
ToolFit MCP Server Preflight Checker is a paid API for AI agents from api.youraitools.co, paid per call via x402, $0.005/call, status unknown (last checked 2026-10-25).
Preflights a remote MCP server URL: checks connectivity, protocol version, OAuth metadata, x402 payment terms, latency, tool count, poisoning patterns, and returns a grade with issues — without ever calling the tools.
Price / call$0.005
Success—
StatusUnknown
How this service works
MCP server checker API. Preflight a public remote MCP server before connecting or paying: does it answer an MCP initialize, which protocol version, sign-in method (OAuth metadata), x402 payment terms, latency, tool count, token cost, provider compatibility, poisoning patterns in tools and instructions, and a grade with issues. Lists tools only, never calls them. Blocked or unresolvable URLs are never charged.
Output
A JSON object containing: a letter grade (e.g. A–F), a verdict string (e.g. 'ok'), total latency in milliseconds, MCP protocol version, tool count, OAuth/sign-in metadata, x402 payment terms, provider compatibility notes, and a list of detected issues including poisoning patterns. Blocked or unresolvable URLs return an error without incurring a charge.
Example use cases
Vetting an unknown MCP server
“I found a public MCP server at https://api.thirdparty.io/mcp/v1 — can you preflight it and tell me its grade, protocol version, latency, and whether it has any security issues before I add it to my agent?”
Checking payment terms before subscribing
“I'm about to pay for access to the MCP server at https://tools.somevendor.com/mcp — can you check if it actually responds, what x402 payment terms it advertises, and give me a compatibility grade?”
Auditing for prompt injection before deployment
“We're deploying an agent that will connect to https://mcp.partner-service.ai/v2 — please preflight it and flag any poisoning patterns in the tool descriptions or instructions so I know if it's safe to use.”
Technical details
Endpoint
GEThttps://api.youraitools.co/toolfit/v1/check?utm_source=zero.xyzWhen to prefer
Use this endpoint when an agent or developer needs to vet an unfamiliar or third-party remote MCP server before connecting, paying, or deploying tools from it. It is the right choice when you need a security-oriented preflight that checks for poisoning, OAuth requirements, x402 cost, and protocol compatibility in a single call — without actually invoking any of the server's tools. Prefer it over a generic HTTP health check when MCP-specific concerns (tool inventory, prompt injection, payment gating) are the priority.
Side effects
- Unresolvable or blocked URL — no charge, returns error indicating the server could not be reached
- MCP server does not respond to initialize handshake — returns failure verdict with latency data
- Server returns unexpected protocol version — flagged as compatibility issue in the grade
- Network timeout — returns partial latency data with a failure verdict
- Invalid URL format supplied — returns validation error before attempting connection
Input
Schema · Request body
| Field | Type | Description |
|---|---|---|
| inputrequired | object | |
| output | object |
Output
Schema · Response
{
"type": "json",
"example": {
"grade": "B",
"tools": 31,
"verdict": "ok",
"latency_ms": {
"total": 361
},
"protocol_version": "2025-06-18"
}
}Tags
x402
Reviews
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