Kairos Partner API

The Partner API lets your users trade prediction markets from their own wallets. Kairos builds every order, setup step and cancel. The user’s wallet signs it, and Kairos submits it to the venue. Your users keep their keys and need no Kairos account. Every endpoint is under /v3. One integration covers Polymarket, Predict.fun and Hyperliquid outcome markets. Polymarket setup needs no gas; Predict.fun asks for one batch of BNB Chain approvals. Reading a wallet’s own orders and positions takes one sign-in signature.

The SDK is optional. Every example in this section has HTTP, Python and JavaScript tabs, and the endpoint reference is an OpenAPI spec you can generate a client from in any language.

Start here

Onboard with Kairos

Get your partner id and base URLs, and plan your launch. Onboarding and go-live.

Place a first order

Set up a wallet, place an order, read it and cancel it, in about 40 lines. Quickstart.

Onboard your users

One-time setup per venue, and where each venue’s funds go. Set up and fund a wallet.

Trade

Show markets, place and cancel orders, and show orders and positions.

Route and fund

Pick the best venue for each order, and get funds where they’re needed. Routing across venues.

Earn

Charge your own fee on each trade, collected on-chain. Partner fees (preview).

What can you build?

Show markets

Prices, charts, and order books. Read-only, no signing.

Let users trade

Set up a wallet, place orders, cancel them.

Show positions

A wallet’s open orders and positions.

How it works

Every action — setup, order, cancel — is the same loop: start it, sign each step the wallet is asked for, send the signature back. Use plain HTTP from any language, the Python client, or the JavaScript SDK, which runs the loop for you:

# 1. Start an order. Kairos answers with the first step to sign.
curl -X POST "$BASE/v3/actions" -H "X-Kairos-Partner-Id: $PARTNER" -H "X-Kairos-Wallet-Api: 2" -H "Content-Type: application/json" \
  -d '{"wallet":"0xUSER","action":{"type":"order","market":"polymarket:0x…","outcome":"Yes","side":"buy","price":"0.52","size":"10"}}'
# {"id":"…","status":"needs_signature","description":"Confirm this Polymarket order",
#  "chainId":"0x89","request":{"method":"eth_signTypedData_v4","params":["0xUSER","{…}"]}}

# 2. The wallet signs `request`. Send the signature back.
curl -X POST "$BASE/v3/actions/$ACTION_ID" -H "X-Kairos-Partner-Id: $PARTNER" -H "X-Kairos-Wallet-Api: 2" -H "Content-Type: application/json" -d '{"signature":"0x…"}'
# The next step, or {"status":"done","result":{"orderId":"…","status":"filled",…}}

from kairos_wallet import run  # the client from /wallets/http

run({"type": "setup"})
run({"type": "order", "market": market, "outcome": "Yes", "side": "buy", "price": "0.52", "size": "10"})

import { createKairos } from '@kairos.trade/sdk'

const kairos = createKairos({ wallet: { baseUrl, partnerId, provider: window.ethereum } })
await kairos.wallet.setup(wallet)
await kairos.wallet.order(wallet, { market, outcome: 'Yes', side: 'buy', price: '0.52', size: '10' })

The same calls trade Polymarket, Predict.fun and Hyperliquid; the venue comes from the market. Each step is a standard EIP-1193 request (eth_signTypedData_v4, personal_sign, or wallet_sendCalls for approvals), so any EIP-1193 wallet works.

Go deeper

Authentication

Partner ids, API keys, the version header and the sign-in token.

What the wallet signs

Every request, per venue, and what to check before showing it.

Venue rules

Chains, collateral and order rules side by side.

Plain HTTP clients

The action loop over HTTP, with complete JavaScript and Python clients.

Endpoint reference

Every /v3 operation, with its request, response and errors, is in the Endpoints group of this tab. It is generated from the OpenAPI spec, which you can download to generate a client in any language.

Endpoints	For
`POST /v3/actions`, `GET` and `POST /v3/actions/{id}`	Setup, orders, cancels and sign-in: start an action, then answer each step
`GET /v3/wallets/{address}`, `/orders`, `/positions`	Readiness, balances, orders and positions
`/v3/fees`, `/v3/fees/settlements`	Partner fees owed, and paying them (preview)
`/v3/trade-plans`	Funded trade plans (preview)
`/v3/onchain-intents`	Split, merge and redeem (preview)

Preview

Coming to production. Trade plans and fees are still being validated; split, merge and redeem run on staging:

Fees

Charge your own fee on top of Kairos’s, collected on-chain.

Trade plans

One signed buy with a cost ceiling, funded from another chain.

Split, merge, redeem

Gasless outcome-token operations on Polymarket.

Get started

Onboard users

Trade

Route and fund

Partner fees

Build

Endpoints

Kairos Partner API

Start here

What can you build?

Show markets

Let users trade

Show positions

How it works

Go deeper

Authentication

What the wallet signs

Venue rules

Plain HTTP clients

Endpoint reference

Preview

Fees

Trade plans

Split, merge, redeem

​Start here

​What can you build?

Show markets

Let users trade

Show positions

​How it works

​Go deeper

Authentication

What the wallet signs

Venue rules

Plain HTTP clients

​Endpoint reference

​Preview

Fees

Trade plans

Split, merge, redeem

Start here

What can you build?

How it works

Go deeper

Endpoint reference

Preview