Place Orders

After confirming that the Market currently accepts orders, you can submit a trade for a specific Outcome Token. Public market data does not require authentication; placing an order is a private operation and requires authentication. Production Base URL:

https://api.dexbuilder.com

1. Read Market Trading Limits

First query the Market and select the Token to trade from outcomes[].token_id:

cURL

curl "https://api.dexbuilder.com/api/v4/prediction/markets/<market_id>"

Then read the public order book:

cURL

curl "https://api.dexbuilder.com/api/v4/prediction/tokens/<token_id>/order_book?depth=20"

Before submitting an order, validate quantity and price against min_order_size and tick_size from the response.

2. Submit an Order

cURL

curl -X POST "https://api.dexbuilder.com/api/v4/broker/prediction/orders" \
  -H "Content-Type: application/json" \
  -H "KEY: ${BROKER_API_KEY}" \
  -H "SIGN: ${SIGN}" \
  -H "Timestamp: ${TIMESTAMP}" \
  -H "X-User-Wallet-Address: ${USER_WALLET}" \
  --data '{
    "token_id": "<token_id>",
    "side": "BUY",
    "price": "0.52",
    "size": "10",
    "total_cost": "5.20",
    "order_type": "GTC",
    "order_mode": "LIMIT",
    "client_order_id": "client-order-001",
    "post_only": false,
    "sell_all": false,
    "expire_time": 0
  }'

Use a Broker API Key and pass a wallet address that belongs to your Broker in X-User-Wallet-Address. Calculate SIGN from the actual request method, path, query string, and body. See Broker API key and signing and Access on behalf of a user.

Request Fields

Field	Description
`token_id`	Outcome Token to trade
`side`	Order side, for example `BUY` / `SELL`
`price`	Limit price, as a decimal string
`size`	Order size, as a decimal string
`total_cost`	Total order cost used by some order modes
`order_type`	Time-in-force: `GTC`, `GTD`, `FOK`, or `FAK`
`order_mode`	Execution mode: `LIMIT` or `MARKET`
`client_order_id`	Optional client idempotency / tracking ID
`post_only`	Whether the order should only provide liquidity as Maker
`sell_all`	Whether to use the full available position when selling
`expire_time`	Expiration time when applicable, Unix seconds

Accepted Response

{
  "order_id": "order-123",
  "client_order_id": "client-order-001",
  "status": "processing",
  "created_at": 1782753357
}

processing means the order request has been accepted for processing; it does not mean the order has been filled. Query the order to check its current REST status.

Pre-Order Checks

The Market must have accepting_orders: true.
token_id should come from the Market’s outcomes array.
size must satisfy min_order_size.
price must conform to tick_size.
Prices, quantities, and amounts should always be represented as strings to avoid floating-point precision issues.
Private requests must use the official authentication scheme.

Getting Started

PerpDEX

Prediction Markets

Event Contracts

1. Read Market Trading Limits

2. Submit an Order

Request Fields

Accepted Response

Pre-Order Checks

​1. Read Market Trading Limits

​2. Submit an Order

​Request Fields

​Accepted Response

​Pre-Order Checks

1. Read Market Trading Limits

2. Submit an Order

Request Fields

Accepted Response

Pre-Order Checks