Official venue APIsAPIfree
Myriad API: what it exposes, how it authenticates, where it stops
Last checked 2026-09-08
Myriad Protocol serves prediction markets through both an AMM and an order book, with a REST API at https://api-v2.myriadprotocol.com/, a staging host at https://api-v2.staging.myriadprotocol.com/, and a public WebSocket at wss://ws.myriadprotocol.com/ws. The order book is deployed on BNB Smart Chain; AMM markets also run on Abstract, Linea and Celo.
It is for agent builders and market makers who want public reads without a key, a CLI built for AI agents, and a staging environment to test against.
What the API exposes
Markets: GET /markets with filtering and sorting, GET /markets/:id, POST /markets/quote for trade quotes, POST /markets/claim for winnings, plus /markets/:id/orderbook and /markets/:id/trades. Orders: POST /orders, GET /orders, DELETE /orders/:orderHash and POST /orders/batch for up to 200 orders atomically. Users: /users/:address/portfolio and /users/:address/events.
Orders are EIP-712 signed under the domain MyriadCTFExchange with the exchange contract as verifyingContract. Prices are integers on a 1-cent tick grid, sides are 0 buy and 1 sell, outcomes 0 Yes and 1 No, and time-in-force accepts GTC, GTD, FOK, FAK and PO.
The WebSocket speaks Centrifugo with public channels for orderbook, trades, prices and markets per network and market; private order and position channels take a subscription token from POST /auth/centrifugo/subscription-token. Tooling includes the Myriad CLI (npm install -g @myriadmarkets/cli), a JavaScript SDK for wallet operations and an MCP server.
Authentication and rate limits
Three modes. Session JWT via Sign-In With Ethereum (GET /auth/nonce, sign, POST /auth/login, Bearer token), supporting EOA and EIP-1271 smart wallets. API key plus secret from POST /auth/api-keys, signing each request with X-Signature = HMAC-SHA256 over timestamp, method, path with query and raw body, with a 30-second timestamp window. Public access for most reads. From August 15, 2026 bare API keys without an HMAC signature are rejected with SIGNATURE_REQUIRED.
Limits: 200 requests per second per IP or key with a key, 30 requests per 10 seconds per IP without, and 200 order placements per 10-second window per trader address, reported through X-RateLimit headers.
Pricing and access
No API fee. Markets on BNB Smart Chain settle in USD1 (some legacy USDT pairs), and other chains use USD-pegged stablecoins. Each market publishes its own fee, treasury_fee and distributor_fee, and endpoints can filter by fee, for example buy_lp_fee_lte=0.01.
Builders can charge frontend fees through POST /markets/quote_with_fee, which requires authentication and whitelisting by the Myriad team, under a builder revenue-sharing program.
Where it falls short
Two trading models and four chains mean market metadata drives which code path you take, and fee levels vary per market.
The HMAC sunset date forces any early bare-key integration to re-sign requests.
No official Python SDK is listed; the CLI and JavaScript SDK are the supported clients.
Who should use it
AI-agent developers who want a CLI with MCP support and public data without onboarding, and market makers on BNB Smart Chain who want batch order placement.
Teams that need a single-chain, single-model venue will find less to configure elsewhere.
Questions about Myriad API
Do I need an API key for the Myriad API?
No for most reads. A key with HMAC signing raises the limit from 30 requests per 10 seconds to 200 per second and is required for authenticated actions.
Which chains does Myriad support?
BNB Smart Chain (mainnet and testnet) for the order book and primary AMM markets, with additional AMM deployments on Abstract, Linea and Celo.
Does Myriad have a staging environment?
Yes: https://api-v2.staging.myriadprotocol.com/ alongside the production host.
What are Myriad fees?
Set per market as LP fee, treasury fee and distributor fee fields on the market object; there is no single published schedule.
Official APIs for building. One book for trading.
Rather trade the spread than build the plumbing? The free Kairos terminal gives you Kalshi, Polymarket and Predict.fun in one order book.