MCP server

mcp-name: io.github.whatevercat-creator/crypto-sentiment-x402

The crypto_sentiment_x402_mcp package exposes the sentiment API as an MCP tool (crypto_sentiment) so Claude Desktop, Claude Code, or any other MCP client can call it directly as part of an agent's normal tool use — no separate HTTP client code needed on the caller's side.

Payment model: the MCP server itself holds a wallet (via Coinbase Developer Platform) and pays the API's x402 price out of that wallet for every call, entirely inside your own local process — invisible to the MCP protocol layer, so it works in Claude Desktop (or any other stock MCP client) exactly like a normal, unpaid MCP server would. There's no free tier — whoever runs this MCP server funds the wallet it uses. If you're handing it to someone else to run, they fund their own wallet, not you.

1. Install

pip install crypto-sentiment-x402-mcp

(uvx crypto-sentiment-x402-mcp works too, and needs no separate install step.)

Don't install this into the same environment as the FastAPI service (requirements.txt). mcp>=2 pulls in a much newer starlette than FastAPI 0.115.0 tolerates (starlette<0.39.0,>=0.37.2) — mixing the two in one venv breaks app/main.py at import time (Router.__init__() got an unexpected keyword argument 'on_startup'). If you're hacking on this repo and want both, give the MCP package its own venv:

python3 -m venv .venv-mcp && source .venv-mcp/bin/activate
pip install -r requirements-mcp.txt cdp-sdk x402

2. Create a CDP API key and fund a wallet

1. Free account + API key at https://portal.cdp.coinbase.com
2. Pick a network:
   • testnet — free Base Sepolia USDC from https://docs.base.org/tools/network-faucets, good for trying this out with no real money.
   • mainnet — real USDC on Base; the wallet needs actual USDC (plus a little ETH for gas) before calls will succeed.
3. The wallet is created automatically the first time the server runs (named by CDP_WALLET_NAME, default crypto-sentiment-mcp-wallet) — run it once locally and check the logs/tool output for the address it prints, then send that address USDC (+ ETH on mainnet) before relying on it inside an agent.

3. Register it with an MCP client

Claude Desktop — add to claude_desktop_config.json:

{
  "mcpServers": {
    "crypto-sentiment": {
      "command": "crypto-sentiment-x402-mcp",
      "env": {
        "CDP_API_KEY_ID": "your-key-id",
        "CDP_API_KEY_SECRET": "your-key-secret",
        "CDP_WALLET_NAME": "crypto-sentiment-mcp-wallet",
        "SENTIMENT_API_URL": "https://crypto-sentiment-x402.onrender.com",
        "X402_NETWORK": "testnet"
      }
    }
  }
}

(That assumes pip install crypto-sentiment-x402-mcp put the console script on PATH for whatever Python Claude Desktop launches with. If you'd rather not rely on PATH, point command at the interpreter and args: ["-m", "crypto_sentiment_x402_mcp"], or, from a repo clone, at mcp_server.py directly, same as before — both still work.)

Claude Code — same shape, either via claude mcp add or a project .mcp.json with the same mcpServers block.

Any other MCP-compatible client works the same way: it just needs a command to launch the server with those env vars set.

4. Use it

Once registered, an agent can call the crypto_sentiment tool with a symbol argument (e.g. BTC) like any other tool — the payment happens transparently inside the call. If a call returns an error field, it's almost always the wallet needing more funds; the response includes the paying wallet's address to check.

Notes

• SENTIMENT_API_URL defaults to the hosted deployment; point it at http://localhost:8000 to test against a local uvicorn app.main:app instead.
• This is a separate process/wallet from client.py (a one-off test script) — both pay the same API, just for different purposes.

License

MIT (see LICENSE-MCP) — this package only. The rest of this repository, including the hosted API in app/, remains All Rights Reserved under the root LICENSE.