Ruff Python Lint API — pay-per-call for AI agents (MCP + x402)

Give any AI agent instant Python linting with ruff. No signup, no API key, no subscription: $0.005 USDC per call, paid automatically over x402 on Base.

• ⚡ Fast: ruff-powered, results in milliseconds

• 🔒 Safe: code is statically analyzed, never executed

• 🤖 Agent-native: MCP tool lint_python for Claude, Cursor, Windsurf, Gemini/Antigravity and any MCP client

• 💸 Pay only for what you use; the facilitator covers gas, so your wallet only needs USDC

Landing page: https://stevensaavedra.com/lint · API: POST https://api.stevensaavedra.com/lint · Verified on PayAPI Market

MCP install

{
  "mcpServers": {
    "ruff-lint": {
      "command": "npx",
      "args": ["-y", "@divine-software-creations/ruff-lint-x402-mcp"],
      "env": { "EVM_PRIVATE_KEY": "0x<key of a Base wallet holding a little USDC>" }
    }
  }
}

Use a dedicated low-balance wallet. $1 of USDC covers 200 lint calls.

Related MCP server: x402-bazaar-mcp

Direct HTTP (x402)

curl -i -X POST https://api.stevensaavedra.com/lint \
  -H 'content-type: application/json' \
  -d '{"code":"import os\nx = 1","language":"python"}'
# -> 402 Payment Required with x402 payment requirements.
# Any x402 client (e.g. @x402/fetch) pays and retries automatically.

Tool

lint_python({ code: string (≤200KB), filename?: string }) → ruff diagnostics (rule code, message, line/column, fix hints).

License

MIT