Compliant Empty

An entirely empty MCP server that passes protocol conformance.

This is a rhetorical artifact: a fully-valid Model Context Protocol server that advertises zero tools, zero resources, and zero prompts. It exists to demonstrate that "we have an MCP" is a valueless claim. MCP is a protocol, not a product. A server can be 100% conformant and do absolutely nothing.

Live instance: https://compliant-empty-mcp-production.up.railway.app/mcp

Run it (stdio)

npx -y github:shinytoyrobots/compliant-empty-mcp

Or clone and build:

git clone https://github.com/shinytoyrobots/compliant-empty-mcp
cd compliant-empty-mcp
npm install
npm run build
npm start

The server speaks JSON-RPC 2.0 over stdio. It responds to initialize, tools/list, resources/list, and prompts/list — the last three with empty arrays. Any other method returns JSON-RPC error -32601 ("Method not found").

Run it (HTTP)

npm run start:http

This starts a Streamable HTTP transport on port 3000 (or $PORT). The MCP endpoint is POST /mcp.

curl -X POST http://localhost:3000/mcp \
  -H "Content-Type: application/json" \
  -H "Accept: application/json, text/event-stream" \
  -d '{"jsonrpc":"2.0","id":1,"method":"initialize","params":{"protocolVersion":"2025-06-18","capabilities":{},"clientInfo":{"name":"curl","version":"0.1"}}}'

Test it

Against the live instance

curl -X POST https://compliant-empty-mcp-production.up.railway.app/mcp \
  -H "Content-Type: application/json" \
  -H "Accept: application/json, text/event-stream" \
  -d '{"jsonrpc":"2.0","id":1,"method":"tools/list","params":{}}'

Response: {"result":{"tools":[]},"jsonrpc":"2.0","id":1}

MCP Inspector

npx @modelcontextprotocol/inspector

In the Inspector UI, set Transport Type to "Streamable HTTP", Connection Type to "Direct", and URL to:

https://compliant-empty-mcp-production.up.railway.app/mcp

Connect as an MCP client

Add to ~/.claude.json (Claude Code) or ~/Library/Application Support/Claude/claude_desktop_config.json (Claude Desktop):

{
  "mcpServers": {
    "compliant-empty-mcp": {
      "type": "url",
      "url": "https://compliant-empty-mcp-production.up.railway.app/mcp"
    }
  }
}

The server will appear as a connected MCP with zero tools. That's the point.

Conformance probe (local)

npm run build
npm run conformance

MCP conformance probe — compliant-empty-mcp

  [PASS] AC-2: initialize returns valid InitializeResult with serverInfo.name
  [PASS] AC-3: tools/list returns { tools: [] }
  [PASS] AC-4: resources/list returns { resources: [] }
  [PASS] AC-5: prompts/list returns { prompts: [] }
  [PASS] AC-6: zero tools, zero resources, zero prompts at all times
  [PASS] AC-7: unsupported method returns error -32601
  [PASS] AC-9: stdio transport is the default and functional
  [PASS] AC-1: server terminates cleanly after stdin close

8/8 checks passed.

Deploy your own

The HTTP server runs on any platform that hosts Node.js. A multi-stage Dockerfile is included.

Railway: import from GitHub. Set the custom start command to npm run start:http (under Service → Settings → Deploy).

Render (free tier): connect this repo, set build command npm install && npm run build, start command npm run start:http.

Fly.io: fly launch auto-detects the Dockerfile.

How empty is it?

The full implementation fits in one file:

import { Server } from "@modelcontextprotocol/sdk/server/index.js";
import { StdioServerTransport } from "@modelcontextprotocol/sdk/server/stdio.js";
import {
  ListToolsRequestSchema,
  ListResourcesRequestSchema,
  ListPromptsRequestSchema,
} from "@modelcontextprotocol/sdk/types.js";

const server = new Server(
  { name: "compliant-empty-mcp", version: "0.1.0" },
  { capabilities: { tools: {}, resources: {}, prompts: {} } },
);

server.setRequestHandler(ListToolsRequestSchema, async () => ({ tools: [] }));
server.setRequestHandler(ListResourcesRequestSchema, async () => ({ resources: [] }));
server.setRequestHandler(ListPromptsRequestSchema, async () => ({ prompts: [] }));

await server.connect(new StdioServerTransport());

That is the entire product. It is a valid MCP server. It does nothing.

The point

Next time a vendor tells you they "have an MCP," ask what's in it.

License

MIT