One API for stocks, crypto and forex trading, built for AI agents

Which markets can one API reach?

No KYC on OpenFinance: agents trade from day one

OpenFinance doesn't ask for identity documents. A new account signs in, gets its embedded wallets and an API key, and trades as soon as the wallet is funded. No broker application and no waiting for approval. A broker-dealer such as Alpaca has to open a brokerage account before live trading.

Two things still apply. If you connect your own IBKR or Robinhood account for options, that broker has already verified you and its rules apply. Buying crypto with a debit card goes through an onramp partner that may ask for ID on its side. Venue rules also hold: Polymarket and some token issuers restrict certain countries, and your local regulations are yours to follow.

One call pattern for three different trades

Every onchain market goes through the same MCP connection and the same tools/call shape. Only the tool name and arguments change, and the exact argument shapes come from the server's own tools/list:

// Same MCP connection (https://api.openfinance.tech/agent/mcp), same JSON-RPC "tools/call".
// Each write runs only after the user sees a quote and replies "yes".

// 1) Onchain stock (spot): find the NVDA token, then swap USDC into it through Relay
{"method":"tools/call","params":{"name":"onchain_search_tokens","arguments":{"query":"NVDA"}}}
{"method":"tools/call","params":{"name":"relay_get_quote","arguments":{"originCurrency":"USDC on Base","destinationCurrency":"<NVDA token from the search>","amount":"100 USDC", "...":"..."}}}
{"method":"tools/call","params":{"name":"relay_execute","arguments":{"...":"the quoted route"}}}

// 2) Hyperliquid perp: long 0.01 BTC with a limit order at 3x
{"method":"tools/call","params":{"name":"hyperliquid","arguments":{"action":"update_leverage","asset":"BTC","leverage":3,"...":"..."}}}
{"method":"tools/call","params":{"name":"hyperliquid","arguments":{"action":"place_order","asset":"BTC","side":"buy","size":"0.01","price":"65000","...":"..."}}}

// 3) Polymarket bet: buy 50 YES shares with a limit at 42¢
{"method":"tools/call","params":{"name":"polymarket","arguments":{"action":"place_order","tokenID":"<YES token id from get_market>","price":0.42,"size":50,"side":"BUY"}}}

Placeholders in <…> are filled from the read calls before them; "..." stands for the remaining fields the tool schema asks for.

OpenFinance vs Alpaca for multi-asset trading

Choose Alpaca if you want real brokerage shares in a US broker account with a paper mode. Choose OpenFinance if you want one connection for onchain stocks, FX, crypto, perps, Polymarket and memecoins without opening a brokerage account, and options through the broker account you already have. More detail: OpenFinance vs Alpaca vs CCXT.