Arbitron API and MCP server
Read-only market data for crypto perpetual futures across the venues Arbitron tracks: current funding rates, funding history, the spread between two venues right now, the scanner's backtested spreads, and the listings calendar. Two doors to the same data: a REST API for programs and an MCP server for AI assistants.
This repository holds the public artefacts of that product so they can be pinned, diffed and cited. The service itself is closed source.
REST in one minute
export ARBITRON_KEY=arb_live_... # https://arbitron.app/settings/api
# The most negative funding on liquid contracts
curl -s "https://arbitron.app/api/v1/funding?max_rate_pct=-0.01&min_volume_usdt=1000000&sort=rate_asc&limit=5" \
-H "Authorization: Bearer $ARBITRON_KEY"
# The spread between venues right now, tradeable pairs only
curl -s "https://arbitron.app/api/v1/spreads?min_volume_usdt=500000&max_spread_pct=3&min_strength=2&fields=symbol,exchange_a,exchange_b,spread_pct,direction" \
-H "Authorization: Bearer $ARBITRON_KEY"
Every response is { "data": ..., "meta": { "as_of", "delayed_seconds", "source", "url", "count", "total", "next_cursor" } }. Errors are RFC 9457 problem details. Rates are percent per settlement. More in examples/.
MCP in one minute
Claude Desktop, Cursor and ChatGPT connect with OAuth 2.1 (sign in with your Arbitron account); a program connects with the same API key as a bearer token. Client configurations are in mcp/clients/. Nine read-only tools: arbitron_search_coins, arbitron_get_funding_rates, arbitron_get_coin_funding, arbitron_get_funding_history, arbitron_get_spreads, arbitron_get_spread_backtest, arbitron_get_listings, arbitron_get_exchanges, arbitron_get_usage.
Plans
The Demo plan is free: 15-minute delayed data, 50 rows per page, no history. Paid plans (Developer, Pro, Business) are live, reach further back, and include commercial use. Details at https://arbitron.app/developers#plans.
Citing
Attribute republished figures as "Data: Arbitron" with a link to meta.url, and keep meta.as_of with the number. Name the exchange and the settlement interval beside any funding rate.
Contents of this repository
openapi/openapi.json: the OpenAPI document as served, refreshed byscripts/refresh.sh.mcp/server.json: the manifest published to the official MCP registry.mcp/clients/: configuration snippets for Claude Desktop, Cursor and ChatGPT.examples/: curl, Python and Node examples.plugin.jsonandmcp.json: the Agent Plugins 1.0 package (Open Plugins standard), so clients and directories that read it discover the MCP server from the repository root..cursor-plugin/: the plugin manifest for the Cursor marketplace.
Files here are licensed under the MIT License. The data the API returns is subject to the terms.