Skip to main content
POST /api/v1/orders Places a new order on the specified exchange.

​
Parameters

​
exchange
string
required
Exchange identifier: polymarket, kalshi, limitless, opinion, or predictfun.

​
Body

​
market_id
string
required
The market to place the order on.
​
outcome
string
required
The outcome to trade (e.g., "Yes" or "No").
​
side
string
required
Order side: "buy" or "sell".
​
price
number
required
Limit price between 0 and 1 (e.g., 0.65 for 65 cents).
​
size
number
required
Order size in contracts/shares.
​
params
object
Optional exchange-specific parameters.
KeyValuesDescription
order_typegtc (default), ioc, fok, gtdTime-in-force / execution type. Unsupported combinations return 501 per exchange.
expirationUnix timestamp (seconds)Required when order_type is gtd. Must be at least 60 seconds in the future. Polymarket only.
​
X-Exchange-Credentials
string
Optional per-request exchange credentials (base64-encoded JSON). When provided, Parsec creates a transient exchange session instead of using stored credentials.Kalshi: { "api_key_id": "...", "private_key": "..." }Polymarket: { "clob_api_key": "...", "clob_api_secret": "...", "clob_api_passphrase": "...", "private_key": "0x..." }For Polymarket transient sessions, private_key is required. The CLOB API fields are optional.

​
Builder fields (optional)

These fields are only used by builders routing orders on behalf of end-users via impersonation.
​
X-Builder-Customer-Id
string
The end-user’s customer_id. Required for builder impersonation.
​
fee_auth
object
EIP-712 fee authorization signed by the end-user’s wallet. Required to collect fees via fee escrow.
​
payer_address
string
End-user’s wallet address (fee escrow payer). Builder-only.
​
signer_address
string
End-user’s signing wallet address. Builder-only.
​
affiliate
string
Affiliate address override. Builder-only.

​
Response

​
(root)
Order
# Limit order (default)
curl -X POST \
  -H "X-API-Key: YOUR_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "market_id": "0x1234abcd",
    "outcome": "Yes",
    "side": "buy",
    "price": 0.65,
    "size": 100
  }' \
  "https://api.parsecapi.com/api/v1/orders?exchange=polymarket"

# IOC order
curl -X POST \
  -H "X-API-Key: YOUR_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "market_id": "0x1234abcd",
    "outcome": "Yes",
    "side": "buy",
    "price": 0.65,
    "size": 100,
    "params": { "order_type": "ioc" }
  }' \
  "https://api.parsecapi.com/api/v1/orders?exchange=polymarket"

# GTD order (auto-expires at timestamp)
curl -X POST \
  -H "X-API-Key: YOUR_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "market_id": "0x1234abcd",
    "outcome": "Yes",
    "side": "buy",
    "price": 0.65,
    "size": 100,
    "params": { "order_type": "gtd", "expiration": "1740600000" }
  }' \
  "https://api.parsecapi.com/api/v1/orders?exchange=polymarket"

{
  "id": "order_abc123",
  "market_id": "0x1234abcd",
  "outcome": "Yes",
  "side": "buy",
  "price": 0.65,
  "size": 100.0,
  "filled": 0.0,
  "status": "open",
  "created_at": "2026-01-26T12:00:00Z",
  "updated_at": null
}