mcp-crypto-arbitrage

An MCP server that exposes CoinGecko crypto market data as tools — get spot prices and find cross-exchange arbitrage spreads without ever needing an API key.

Tools

Related MCP server: CoinGecko MCP Server

Prerequisites

• Node.js 18+

• Nothing else — CoinGecko's public API works with no key. Optionally set COINGECKO_API_KEY (free Demo key) for a higher rate limit (100 calls/min vs the public tier's much lower limit)

Installation

Quick install

The package is published on npm, so these register it in one step — no cloning or building required:

Claude Code:

claude mcp add crypto-arbitrage -- npx -y mcp-crypto-arbitrage

Codex CLI:

codex mcp add crypto-arbitrage -- npx -y mcp-crypto-arbitrage

Manual config (any stdio MCP client)

Most clients that support stdio MCP servers (Claude Desktop, Cursor, Windsurf, etc.) use this same config shape — add it to whichever config file your client expects:

{
  "mcpServers": {
    "crypto-arbitrage": {
      "command": "node",
      "args": ["/absolute/path/to/mcp-crypto-arbitrage/dist/index.js"]
    }
  }
}

Add COINGECKO_API_KEY under env if you have one.

Restart your client, then try asking:

"What's the price of bitcoin and ethereum right now?"

"Is there an arbitrage opportunity on solana above 0.5%?"

"Scan the top 10 coins for cross-exchange spreads"

How it works

MCP client (Claude, Inspector, ...)
        │  stdio, JSON-RPC
        ▼
  McpServer (src/server.ts)
        │
        ▼
  tools/*.ts     — one file per tool: Zod schema + handler, formats the reply
        │
        ▼
  endpoints/*.ts — one file per CoinGecko endpoint: typed request + response
        │
        ▼
  apiClient.ts   — optional demo-key header, CoinGecko error/rate-limit parsing
        │
        ▼
  client.ts      — generic fetch wrapper, timeout, HTTP error handling
        │
        ▼
  CoinGecko REST API

Each layer knows nothing about the one above it. client.ts doesn't know CoinGecko exists; endpoints/ doesn't know MCP exists. Adding a new tool means one new file in endpoints/, one new file in tools/, one line in tools/index.ts — nothing else changes.

Tool arguments are validated with Zod before any handler runs — a malformed request never reaches the API.

find_arbitrage and scan_top_coins compare only USD/USDT-quoted markets from CoinGecko's /coins/{id}/tickers endpoint — the widest gap between the lowest and highest last-traded price across those markets is reported as the spread. This is raw market-data spread, not a tradeable guarantee: it ignores withdrawal/deposit friction, exchange fees, and execution slippage.

Development

git clone https://github.com/abe-source/mcp-crypto-arbitrage.git
cd mcp-crypto-arbitrage
npm install
npm run build   # compile TypeScript
npm run lint     # check formatting + lint rules
npm run check    # lint + format + fix, in place

Test locally with the MCP Inspector:

npx @modelcontextprotocol/inspector --cli node dist/index.js --method tools/call --tool-name get_coin_prices --tool-arg coins=bitcoin,ethereum

License

MIT