Openapi Validator

Validation REST API MCP

Validate an OpenAPI 3.x (or Swagger 2.0) document given as JSON or YAML and return a report with errors, warnings, and summary info (title, version, path count, operation count). Errors cover a missing version field, missing info.title or info.version, a missing paths object, paths that do not start with "/", and operations without responses. Warnings cover missing operationId, Swagger 2.0 input, non-3.x versions, and component schemas with no type, $ref, or composition keyword.

This page documents the MCP tool findutils:openapi_validator. See the REST reference →

Use in the browser View as Markdown

Call it over MCP

Tool name findutils:openapi_validator · no API keys · 120 requests/min per IP

Claude Code

claude mcp add findutils --transport http https://mcp.findutils.com/

Claude Desktop — claude_desktop_config.json

{
  "mcpServers": {
    "findutils": {
      "url": "https://mcp.findutils.com/"
    }
  }
}

Raw JSON-RPC (any MCP client) — verified example

curl -X POST https://mcp.findutils.com/ \
  -H "Content-Type: application/json" \
  -d '{
    "jsonrpc": "2.0",
    "id": 1,
    "method": "tools/call",
    "params": {
      "name": "openapi_validator",
      "arguments": {
        "spec": "{\"openapi\":\"3.0.3\",\"info\":{\"title\":\"Sample API\",\"version\":\"1.0.0\"},\"paths\":{\"/users\":{\"get\":{\"operationId\":\"listUsers\",\"responses\":{\"200\":{\"description\":\"ok\"}}}}}}"
      }
    }
  }'

Input schema

Argument	Type	Required	Description
spec	string	yes	The OpenAPI or Swagger document as JSON or YAML text.

Example arguments (verified)

{
  "spec": {
    "openapi": "3.0.3",
    "info": {
      "title": "Sample API",
      "version": "1.0.0"
    },
    "paths": {
      "/users": {
        "get": {
          "operationId": "listUsers",
          "responses": {
            "200": {
              "description": "ok"
            }
          }
        }
      }
    }
  }
}

Arguments that carry JSON as a string are shown decoded for readability. The Copy button copies the exact wire arguments.

Also a REST endpoint

The same tool answers plain HTTP at POST /api/tools/openapi-validator/execute — no key, 60 requests/min.

Open the REST reference for Openapi Validator →

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