✅ mcp-compliance-lite

✅ mcp-compliance-lite

MCP spec conformance tester. Validate any MCP server against the Model Context Protocol specification: JSON-RPC 2.0 compliance, initialize handshake, tool schema validation, and error code correctness.

In 2026, there are 9,400+ public MCP servers — but "almost none are tested against the spec." The official MCP roadmap lists "Conformance Test Suites" as future work. mcp-compliance-lite fills the gap: 14 spec checks across 4 categories, zero dependencies.

Complements mcp-guard (security scanner — checks what tools can do) — mcp-compliance-lite checks whether the server follows the protocol spec.

Features

• 📋 14 spec checks across 4 categories: JSON-RPC, handshake, tools, errors
• 🔌 Live testing — run against any MCP server via stdio
• 📄 Trace file validation — check pre-recorded JSONL traces
• 🎨 CLI — human-readable report or JSON output
• ✅ CI-ready — exits non-zero on non-compliance
• 🚫 Zero runtime dependencies

Quick Start

npm install -g mcp-compliance-lite

Usage

Test a live server

mcp-compliance test npx @anthropic/mcp-server
mcp-compliance test python my_mcp_server.py
mcp-compliance test node dist/server.js --json

Validate a pre-recorded trace

# Record a trace
mcp-probe tools my-server | tee trace.jsonl

# Check compliance
mcp-compliance check trace.jsonl

List spec rules

mcp-compliance rules

Output:

COMPLIANT (with warnings)  12/14 passed  (86%)  0 errors, 2 warnings

  ✓ json-rpc     JSON-RPC version must be '2.0'
  ✓ json-rpc     All responses include a request id
  ✓ handshake    Initialize response is valid
  ✓ handshake    Initialize must include protocolVersion
  ✓ handshake    Initialize must include capabilities
  ⚠ handshake    Server info should include a name
     serverInfo.name is missing or empty
  ⚠ tools        Server must respond to tools/list
     No tools/list response found in trace
  ...

Spec Checks

Programmatic API

import { validate, runServer } from "mcp-compliance-lite";

// Validate a trace
const report = validate(messages);
console.log(report.summary);

// Run against a live server
const { messages, errors } = await runServer("python", ["server.py"]);
const report = validate(messages);

Development

git clone https://github.com/alvabillwu/mcp-compliance-lite.git
cd mcp-compliance-lite
npm install && npm test

🔗 Ecosystem

Part of the alvabillwu AI/LLM DevTools suite:

• mcp-probe — CLI probe to inspect any MCP server
• mcp-guard — Security scanner for MCP server tool manifests
• mcpindex — Searchable index and discovery tool for MCP servers

License

MIT © alvabillwu