BALLDONTLIE MCP Server

Remote Model Context Protocol server for the BALLDONTLIE sports API. The tool catalog is generated from the vendored public OpenAPI specifications so endpoint methods, paths, parameters, and constraints stay aligned with the API source.

The current generated surface contains 505 tools from 27 specifications: Account, ATP, Bundesliga, college baseball, Counter-Strike, Dota 2, EPL, F1, FIFA World Cup, La Liga, Ligue 1, League of Legends, MLB, MLS, MMA, NBA, NCAAB, NCAAF, NCAAW, NFL, NHL, PGA, Serie A, UCL, Valorant, WNBA, and WTA. /health reports the authoritative runtime count and deployed revision.

Authentication

Every MCP request requires a BALLDONTLIE API key:

Authorization: Bearer YOUR_API_KEY

Initialization, tool listing, authenticated documentation, and API operations that are public outside the MCP validate the supplied key before proceeding. Other tool calls forward only the Authorization header to the corresponding authenticated BALLDONTLIE endpoint.

Public service metadata is limited to /health and /.well-known/mcp-config. /api/docs requires a valid API key.

Sensitive Account tools

The complete Account API surface is registered, but the following tools are disabled by default:

• account_signup
• account_rotate_api_key
• account_change_subscription
• account_cancel_subscription
• account_create_checkout
• account_get_billing_portal

They can create credentials, change billing state, or return sensitive hosted billing-session URLs. A deployment must set ENABLE_SENSITIVE_ACCOUNT_TOOLS=true exactly to enable them. Enabling the flag means those values may intentionally enter the authenticated caller's MCP transcript. Other spellings, casing, or whitespace fail closed.

account_get_me remains available but always omits the api_key response field.

MCP request example

curl https://mcp.balldontlie.io/mcp \
  -H 'Content-Type: application/json' \
  -H 'Authorization: Bearer YOUR_API_KEY' \
  -d '{
    "jsonrpc": "2.0",
    "id": 1,
    "method": "tools/call",
    "params": {
      "name": "nba_get_teams",
      "arguments": {}
    }
  }'

Use tools/list to retrieve the current catalog, input schemas, and MCP read-only/destructive annotations.

Development

npm ci
npm run check:openapi
npm test
npm run build

The tests independently compare every generated operation and input against all vendored specifications. They also cover legacy tool-name compatibility, exact array query serialization, path/body dispatch, credential-safe errors and logs, API-key validation limits, and Account safety controls. Tests never call a live Account mutation.

Updating from the API source

1. Copy balldontlie-2/marketing/public/openapi.yml to openapi.yml.
2. Copy every balldontlie-2/marketing/public/openapi/*.yml file into openapi/.
3. Update scripts/openapi-source.json to the source API commit.
4. Run npm run generate:openapi.
5. Run npm test and npm run build.

Generated src/tools/*.ts, src/schemas/*.ts, and registry files are checked in and must not be edited manually. Runtime does not parse YAML and has no production YAML-parser dependency.

Configuration

Variable	Default	Purpose
PORT	3000	HTTP port
BACKEND_API_URL	https://api.balldontlie.io	BALLDONTLIE API base URL
API_TIMEOUT	30000	Upstream timeout in milliseconds
ENABLE_DEBUG	false	Logs only method, query-free path, and query-field count
ENABLE_SENSITIVE_ACCOUNT_TOOLS	false	Enables sensitive Account tools only when exactly true
TRUST_PROXY_HOPS	1 in production, 0 otherwise	Validated trusted proxy hop count; only 0 or 1 is accepted
ENABLE_TRACING	false	Enables Datadog tracing when an agent host is configured

Authorization values, query values, request bodies, raw upstream errors, API-key responses, and hosted billing-session URLs are excluded from server logs and tracing tags.