MCP Endpoint Lint - handshake, tool schemas, JSON-RPC errors

{
  "_meta": {
    "io.modelcontextprotocol.registry/official": {
      "status": "active",
      "isLatest": true,
      "updatedAt": "2026-09-07T00:44:27.395557Z",
      "publishedAt": "2026-09-07T00:44:27.395557Z",
      "statusChangedAt": "2026-09-07T00:44:27.395557Z"
    }
  },
  "server": {
    "name": "dev.workers.pathwren.www/mcp-endpoint-lint",
    "_meta": {
      "io.modelcontextprotocol.registry/publisher-provided": {
        "auth": "none",
        "docs": "https://www.pathwren.workers.dev/c/mcp-registry-official/mcp.html",
        "tools": [
          {
            "name": "handshake_report",
            "search": "does this MCP endpoint's initialize work, and is it idempotent"
          },
          {
            "name": "tools_list_report",
            "search": "schema-validate every tool an MCP endpoint advertises"
          },
          {
            "name": "error_conformance",
            "search": "does it answer -32601/-32602, or an HTML 500"
          },
          {
            "name": "discovery_report",
            "search": "what an MCP client looks for before it dials, and what answered"
          },
          {
            "name": "score_card",
            "search": "score an MCP endpoint out of 100 in one call"
          },
          {
            "name": "whoami",
            "search": "who is calling - no arguments"
          },
          {
            "name": "example",
            "search": "run the worked example - no arguments"
          }
        ],
        "example": {
          "curl": "curl -s -X POST https://www.pathwren.workers.dev/c/mcp-registry-official/mcp/lint -H 'content-type: application/json' -H 'accept: application/json, text/event-stream' -d '{\"jsonrpc\":\"2.0\",\"id\":1,\"method\":\"tools/call\",\"params\":{\"name\":\"whoami\",\"arguments\":{}}}'",
          "note": "whoami takes no arguments at all and answers about the request you just sent - user-agent, address, what our classifier makes of it. Every tool here accepts {} and answers with its own documented worked example, run against a built-in fixture: no outbound request is made and no third party is touched. Send the request below verbatim. To lint a real endpoint, pass your own url - this server fetches the URL you give it, and only that.",
          "request": {
            "id": 1,
            "method": "tools/call",
            "params": {
              "name": "whoami",
              "arguments": {}
            },
            "jsonrpc": "2.0"
          },
          "endpoint": "https://www.pathwren.workers.dev/c/mcp-registry-official/mcp/lint",
          "transport": "streamable-http"
        },
        "pricing": "free",
        "keywords": [
          "mcp",
          "lint",
          "validator",
          "conformance",
          "health check",
          "monitoring",
          "json-rpc",
          "json schema",
          "protocol version",
          "streamable http",
          "oauth-protected-resource",
          "rfc 9728",
          "discovery",
          "score card",
          "markdown",
          "markdown docs",
          "free",
          "no api key",
          "no auth"
        ],
        "markdown": {
          "note": "Everything this server answers from is also readable without JSON-RPC and without an MCP client: every page of the host is a plain markdown file at the same address with .md — also .mdx, <page>.html.md, <page>.html.mdx, or send Accept: text/markdown to the .html page. No key, no JavaScript, CC0. The registry caps `description` at 100 characters, which is why this sentence lives here.",
          "index": "https://www.pathwren.workers.dev/c/mcp-registry-official/sitemap.md",
          "example": "curl -s https://www.pathwren.workers.dev/c/mcp-registry-official/mcp-lint.md",
          "canonical": "the HTML page; each mirror carries Link: rel=\"canonical\" back to it"
        },
        "publisher": "Pathwren - an independent, non-commercial automated project",
        "dataLicense": "CC0-1.0",
        "authentication": "none - no key, no account, no OAuth",
        "outbound_requests": {
          "only_to": "the URL supplied by the caller in the tool arguments",
          "refuses": "its own publisher, ephemeral tunnel and preview hostnames, IP literals, private names, URLs carrying credentials, non-HTTP schemes and unusual ports - before any socket is opened",
          "storage": "none - a caller's URL is never written to a database, a log line or a metric",
          "makes_them": true,
          "timeout_ms": 6000,
          "user_agent": "growth-loop/1.0 (+https://www.pathwren.workers.dev/mcp-lint.html)",
          "rate_limited": "per caller, per target host, and per edge location",
          "zero_argument_calls": "run against a built-in fixture and make no outbound request at all"
        }
      }
    },
    "icons": [
      {
        "src": "https://www.pathwren.workers.dev/c/mcp-registry-official/icon.png",
        "sizes": [
          "256x256"
        ],
        "mimeType": "image/png"
      }
    ],
    "title": "MCP Endpoint Lint - handshake, tool schemas, JSON-RPC errors",
    "$schema": "https://static.modelcontextprotocol.io/schemas/2025-12-11/server.schema.json",
    "remotes": [
      {
        "url": "https://www.pathwren.workers.dev/c/mcp-registry-official/mcp/lint",
        "type": "streamable-http"
      }
    ],
    "version": "1.3.0",
    "websiteUrl": "https://www.pathwren.workers.dev/c/mcp-registry-official/mcp-lint.html",
    "description": "{\"jsonrpc\":\"2.0\",\"id\":1,\"method\":\"tools/call\",\"params\":{\"name\":\"whoami\",\"arguments\":{}}} free no key"
  }
}