oddsrelay-mcp

An MCP server that gives an AI assistant read access to OddsRelay: matched boards, the prices for one event, and the sport, event, bookmaker and coverage lists behind them. It is read-only, and every call that spends tokens is priced first and refused above a cap, so an assistant cannot run down your token balance by accident.

It works with Claude Desktop, Claude Code, Cursor and any other client that starts MCP servers over stdio, and it is built on the oddsrelay TypeScript client.

API docs: https://oddsrelay.io/docs

Set up

You need an OddsRelay API key, which you create from your account at https://oddsrelay.io. The server reads the key from ODDSRELAY_KEY. The bundle sets it for you; the other routes set it in your MCP client's config and need Node 18 or later.

Claude Desktop (one-click bundle)

Download oddsrelay-mcp.mcpb from the latest release and double-click it to install it in Claude Desktop, which asks for one setting: your API key. The setting is marked sensitive, so Claude Desktop masks it, and it passes the key to the server as ODDSRELAY_KEY. The bundle carries everything the server needs and runs on the Node built into Claude Desktop, so you need no Node of your own.

Claude Code

claude mcp add --transport stdio oddsrelay --env ODDSRELAY_KEY=your_key_here -- npx -y oddsrelay-mcp

Claude Desktop (config file)

Settings, Developer, Edit Config opens claude_desktop_config.json. Add the server, then restart Claude Desktop:

{
  "mcpServers": {
    "oddsrelay": {
      "command": "npx",
      "args": ["-y", "oddsrelay-mcp"],
      "env": { "ODDSRELAY_KEY": "your_key_here" }
    }
  }
}

Cursor

Add the same mcpServers block to ~/.cursor/mcp.json (every project) or .cursor/mcp.json (one project).

The key sits in that config file as plain text, so keep the file out of anything you commit.

First questions

Ask your assistant:

Using OddsRelay, which bookmakers carry tennis on the standard board?

That calls coverage, which costs no tokens. Then:

Show the OddsRelay standard board for soccer at Ladbrokes and William Hill, first five events.

The assistant finds the bookmaker keys with bookmakers, then calls odds, which is priced before it runs.

Tools

The token cap

odds and event_odds take a max_tokens argument with a small default. Before each call the server asks the API what the call would cost (a quote, which spends nothing). If it would cost more than max_tokens, the server makes no call, spends nothing and tells the assistant the price, so the assistant can narrow the filters or ask you before it tries again with a higher max_tokens.

odds always takes one sport and the bookmakers you name, so each call stays narrow. The cost is set by the filters you send; cutting the reply to limit rows does not change it. Every reply from these two tools carries tokens: what the call cost and what is left.

Both tools only read, but their MCP annotations mark them as calls with a cost rather than read-only, so a client that asks before such calls will ask you each time. event_odds reads the raw board, so it needs a key that can read raw odds.

Replies

Replies are compact JSON. Long lists are cut to limit rows (each tool has its own default) and to a size an assistant can read in one go, with a more note saying how many rows were left out and what to change to see them. Paged tools return next_cursor, which the assistant passes back as cursor; a page cut short goes on from the first row not shown.

Errors come back as tool errors with the API's error code and, where the API sends them, the values it accepts: ask for an unknown bookmaker and the error lists the keys it accepts.

Your key

The server reads the key only from ODDSRELAY_KEY and sends it only to https://api.oddsrelay.io, in the Authorization header. It never puts the key in a tool reply or an error: if an error ever echoed it, it would be replaced with [hidden]. The server logs nothing.

What it does not do

No tool writes anything, reads or writes files, or calls any host but the OddsRelay API.

Develop

npm ci
npm test

The tests run the server against a stubbed fetch and make no network calls. npm run bundle builds oddsrelay-mcp.mcpb from dist and the installed dependencies: manifest.json describes the bundle, and .mcpbignore keeps sources, tests and development packages out of it. To try the built server by hand, npx @modelcontextprotocol/inspector node dist/cli.js opens it in the MCP Inspector.

Links

• Docs: https://oddsrelay.io/docs
• Website: https://oddsrelay.io
• TypeScript client: https://github.com/oddsrelay/oddsrelay-js
• Contact: hello@oddsrelay.io

License

MIT