designesy-mcp

A read-only stdio MCP server exposing designesy.org's design-intelligence infrastructure as native agent tools.

Zero external dependencies. Pure Python stdlib. Implements the Model Context Protocol JSON-RPC 2.0 over stdio.

Quick start (one command)

uvx designesy-mcp

That's it. uvx fetches the package from PyPI, creates an ephemeral environment, and launches the stdio MCP server. No virtualenv, no pip install, no git clone. The server is ready to speak JSON-RPC 2.0 on stdin/stdout immediately.

Don't have uv? Install it once: curl -LsSf https://astral.sh/uv/install.sh | sh (macOS/Linux) or powershell -c "irm https://astral.sh/uv/install.ps1 | iex" (Windows). Or use pipx run designesy-mcp as an equivalent one-liner.

MCP client config

uvx (recommended — no install step)

{
  "mcpServers": {
    "designesy": {
      "command": "uvx",
      "args": ["designesy-mcp"]
    }
  }
}

pip install (traditional)

pip install designesy-mcp

{
  "mcpServers": {
    "designesy": {
      "command": "designesy-mcp"
    }
  }
}

python -m (module form)

{
  "mcpServers": {
    "designesy": {
      "command": "python",
      "args": ["-m", "designesy_mcp_server"]
    }
  }
}

No arguments needed. The server speaks JSON-RPC 2.0 over stdin/stdout.

Tools (11)

The server exposes 11 tools, all fetched live from https://www.designesy.org/:

Read-only discovery

Executable verification

Resources (7)

The server also exposes 7 MCP resources (read-only URIs):

The 36-check verification engine

designesy_score runs 36 deterministic checks across 13 weighted categories:

No LLM. No roast. The same engine scores designesy.org itself — in public, at 99.1% A.

Caching

All responses are cached with a 5-minute TTL. The server only fetches public, machine-readable exports from designesy.org via HTTPS. It does not read local files, credentials, or source roots.

Safety

Read-only. This server never writes anywhere. It does not execute code, mutate files, or access credentials.

Provenance

All data is fetched live from:

• https://www.designesy.org/open.json
• https://www.designesy.org/contracts/design-system.json
• https://www.designesy.org/kits/design-review.json
• https://www.designesy.org/contracts/skill
• https://www.designesy.org/.well-known/agent.json
• https://www.designesy.org/llms.txt
• https://www.designesy.org/llms-full.txt

License

MIT

Links

• Homepage
• Agent Install — one-command uvx designesy-mcp
• Repository
• MCP Registry entry
• Changelog
• Design-system contract
• Leaderboard
• Methodology