{"uid":"cap_ScH6oYEiGCgsgWs4UR-i9","slug":"toolfit-mcp-server-preflight-checker-de3b8776","name":"ToolFit MCP Server Preflight Checker","description":"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.","url":"https://api.youraitools.co/toolfit/v1/check?utm_source=zero.xyz","method":"GET","headers":{},"bodySchema":{"type":"object","$schema":"https://json-schema.org/draft/2020-12/schema","required":["input"],"properties":{"input":{"type":"object","required":["type","method"],"properties":{"type":{"type":"string","const":"http"},"method":{"enum":["GET"],"type":"string"},"queryParams":{"type":"object","required":["url"],"properties":{"url":{"type":"string","description":"Public remote MCP server URL (Streamable HTTP, https), e.g. https://api.youraitools.co/mcp/hub. ToolFit only lists its tools."}},"description":"Search intents: mcp server check, test mcp server, mcp preflight, mcp oauth check, remote mcp validator, mcp server health"}},"additionalProperties":false},"output":{"type":"object","required":["type"],"properties":{"type":{"type":"string"},"example":{"type":"object","properties":{"grade":{"type":"string"},"tools":{"type":"number"},"verdict":{"type":"string"},"latency_ms":{"type":"object"},"protocol_version":{"type":"string"}}}}}}},"responseSchema":{"type":"json","example":{"grade":"B","tools":31,"verdict":"ok","latency_ms":{"total":361},"protocol_version":"2025-06-18"}},"example":null,"exampleRequest":null,"tags":["x402"],"displayCostAmount":"0.005","displayCostAsset":"USDC","priceDynamic":false,"priceHint":null,"priceStatus":"priced","priceSource":"probe","requiresHandshake":false,"reviewCount":0,"rating":{"score":"0.00","successRate":"0.00","reviews":0,"stars":null,"state":"unrated"},"availabilityStatus":"unknown","priceObserved":null,"sessionDeposit":null,"pricing":{"kind":"static","summary":"$0.005/call","primary":{"kind":"static","protocol":"x402","network":"base","amountUsd":"0.005","per":"call","confidence":"exact"},"accepted":[{"kind":"static","protocol":"x402","network":"base","amountUsd":"0.005","per":"call","confidence":"exact"}]},"paymentMethods":[{"uid":"pm_5i1vMZfqPsUowUtXWpHSl","protocol":"x402","methodType":"crypto","chain":"base","mode":"charge","costAmount":"0.005","costPer":"request","priority":0,"asset":"0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913","unit":"request","depositMicros":null,"planRef":null}],"brandName":null,"brandSlug":null,"brandBaseUrl":null,"brandDocsUrl":null,"whatItDoes":"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.","exampleAgentPrompt":"Before I connect to https://api.example.co/mcp, can you run a preflight check on it — I want to know its grade, whether it needs OAuth or payment, how many tools it has, and if there are any poisoning or compatibility issues?","exampleUseCases":[{"title":"Vetting an unknown MCP server","prompt":"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?"},{"title":"Checking payment terms before subscribing","prompt":"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?"},{"title":"Auditing for prompt injection before deployment","prompt":"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."}],"resultDescription":"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.","failureModes":["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"],"whenToPreferThis":"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.","instructions":null,"reviewSummary":null,"reviewSummaryHighlights":null,"reviewSummaryConcerns":null,"reviewSummaryGeneratedAt":null,"activationCount":0,"lastUsedAt":null,"lastSuccessfullyRanAt":null,"lastHealthCheckAt":"2026-10-25T12:30:17.569Z","isFirstParty":false,"canonicalSlug":"toolfit-mcp-server-preflight-checker-de3b8776"}