What Is Kairos? Prediction Market Trading Platform

Kairos is a unified trading platform that connects you to every major prediction market and perpetuals venue through a single, consistent API surface. Instead of integrating with Polymarket, Kalshi, Predict.fun, and Hyperliquid separately — each with its own authentication, data formats, and order flow — you use Kairos once and trade everywhere.

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Supported Venues

Kairos routes orders and streams data across the following venues:

• Polymarket — the world’s largest on-chain prediction market (USDC on Polygon)
• Kalshi — regulated US prediction market (CFTC-designated contract market)
• Predict.fun — prediction market with native combo/parlay support
• Opinion — emerging prediction market venue
• Hyperliquid — perpetuals DEX for leveraged positions on crypto and more

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The Four APIs

Kairos exposes four purpose-built APIs. Every API lives at its own base URL and is documented separately, but they share the same authentication scheme and data conventions. Together these APIs expose 155 endpoints covering every stage of the trading lifecycle.

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Key Capabilities

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Market Data API

The Market Data API (md.kairos.trade) is completely free — no account, no API key, no rate-limit headers to manage for casual use. It provides:

• Markets — paginate active markets for any provider, fetch by ID, or resolve venue-specific identifiers
• Candles — OHLCV series for a single contract or batched up to 200 contracts in one request
• Trades — recent tape and aggregate volume/pressure metrics
• Marks — latest mark price (last-trade price) for up to 200 contract/token pairs
• Resolutions — batch resolution fractions and full lifecycle timelines
• Perpetuals — live snapshots for Hyperliquid and other perp venues

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Data API

The Data API (data.kairos.trade) is the full Kairos data plane. Authenticated callers can access:

• Search — full-text market search, autocomplete, URL resolution, and screener queries
• Discover — paginated event-grouped market lists, trending movers, and expiring-soon feeds
• Sports — cross-platform matched markets, live games, tournament brackets, and TxOdds fixtures
• Trader Analytics — per-wallet PnL history, positions, and trade history (some endpoints free)
• PnL — merged PnL across wallets and providers, live per-market hover data
• Candles & Trades — higher-throughput batched candle and trade endpoints with broader filters

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Execution API

The Execution API (execution.kairos.trade) handles every order lifecycle event:

• Orders — submit, list, fetch, cancel single or batch, cancel-all, fee quotes
• Routing — price and execute cross-venue split orders across linked market pairs
• Combos — quote, execute, cash out, and redeem Polymarket parlays
• Onboarding — enable trading on each venue (Polymarket CLOB credentials, Kalshi API keys, Predict.fun approvals, Opinion)
• Self-custody — EIP-712 intent/submit flow so your private key never leaves your client
• Hyperliquid — typed-data withdraw and spot↔perp transfer helpers
• CTF — split, merge, and redeem outcome token sets

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Agora Auction API

The Agora Auction API (agora.kairos.trade) is a private institutional venue for block-size trades:

• Create and manage private auctions with capacity preflight checks
• Invite makers to submit or revise firm, executable quotes
• Stream the complete audit timeline over WebSocket
• Role-filtered views ensure each participant sees only what they’re entitled to

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Machine-Readable Specs

If you’d rather generate a client from an OpenAPI spec, download the YAML files directly:

• agora.yaml
• data-api.yaml
• execution.yaml
• market-data-api.yaml
• kairos.json — combined spec

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Next Steps