> ## Documentation Index
> Fetch the complete documentation index at: https://docs.limitless.exchange/llms.txt
> Use this file to discover all available pages before exploring further.
# Create Order
> Creates a buy/sell order for prediction market positions. Requires signed order data.
Before creating orders:
1. Fetch market data via [Get Market Details](/api-reference/markets/get-market) to get venue and token IDs
2. Sign the order using [EIP-712](/developers/eip712-signing) with `venue.exchange` as `verifyingContract`
3. Ensure you have [token approvals](/developers/venue-system#required-token-approvals) set up
Order creation can be temporarily restricted during maintenance. In `post_only`, only orders with `postOnly: true` are accepted. In `cancel_only` or `disabled`, new orders return `503 Service Unavailable`. Check [Maintenance Mode](/developers/maintenance-mode) before sending orders.
### Optional Fields
| Field | Type | Description |
| --------------- | --------- | -------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
| `clientOrderId` | `string` | Idempotency key (max 128 chars). If a duplicate is submitted, the server returns `409 Conflict`. |
| `onBehalfOf` | `number` | Profile ID of the sub-account to place the order for. Requires a [scoped API token](/developers/authentication#scoped-api-tokens-hmac) with `trading` scope and a partner relationship with the target profile. The `maker` and `signer` in the order must match the sub-account's wallet address. |
| `postOnly` | `boolean` | GTC orders only. When `true`, the order is rejected if it would immediately match. Guarantees the order rests on the book as a maker order. Default `false`. |
| `timestamp` | `number` | Optional client-stamped Unix time in milliseconds for receive-window checks. Top-level request field; not part of the signed `order`. |
| `recvWindow` | `number` | Optional maximum accepted order age in milliseconds. Valid range: `1` to `10000`. If omitted, no receive-window check is applied. Top-level request field; not part of the signed `order`. |
| `stpPolicy` | `string` | Self-trade prevention policy. Values: `cancel_maker`, `cancel_taker`, `cancel_both`. Default `cancel_maker`. Top-level request field; not part of the signed `order`. |
### Receive Window
`POST /orders` supports optional receive-window controls for clients that want freshness checks on order submission. Send these fields at the top level of the request body, next to `order`, `orderType`, and `marketSlug`; never put them inside the EIP-712 signed `order` object.
```json theme={null}
{
"order": {
"...": "signed order fields"
},
"orderType": "GTC",
"marketSlug": "btc-100k",
"timestamp": 1779870000000,
"recvWindow": 1500
}
```
| Field | Description |
| ------------ | -------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
| `timestamp` | Client order creation time as Unix milliseconds. Direct API callers should send this with `recvWindow` when they want client-to-server freshness checks. |
| `recvWindow` | Maximum accepted age, in milliseconds, between `timestamp` and the server receive time. Valid range: `1` to `10000`. If omitted, no receive-window check is applied. |
Keep trading hosts NTP-synced. If the timestamp is too far in the future or older than the receive window, the API returns `425 Too Early`. Do not retry the same signed payload after a `425`; build and sign a fresh order.
### Self-Trade Prevention
`POST /orders` can reject or cancel orders that would match against your own resting order on the same token.
```json theme={null}
{
"order": {
"...": "signed order fields"
},
"orderType": "GTC",
"marketSlug": "btc-100k",
"stpPolicy": "cancel_taker"
}
```
| Policy | Result |
| -------------- | ------------------------------------------------------------------------------------ |
| `cancel_maker` | Default. Cancel your conflicting resting order and continue with the incoming order. |
| `cancel_taker` | Reject the incoming order before it self-trades. |
| `cancel_both` | Cancel your conflicting resting order and reject the incoming order. |
With `cancel_maker`, matching continues against the remaining non-self liquidity, and limit orders still never execute past their limit price.
**Outcomes on the placement response:**
* A rejected taker (`cancel_taker` / `cancel_both`) returns `settlementStatus: "CANCELED"` with `reason: "STP_TAKER_REJECTED"`.
* A `cancel_maker` taker lists the canceled resting order IDs in `stpMakerCancels` and keeps its normal status (`UNMATCHED` when nothing else fills it); no `reason` is set.
`stpPolicy` is a top-level request field. Do not include it inside the EIP-712 signed `order` object.
**SDK support.** Self-trade prevention is available in the TypeScript, Python, Rust, and Go SDKs — pass the policy on order creation and read the outcome from the `execution` object on the response. See [TypeScript](/developers/sdk/typescript/orders#self-trade-prevention), [Python](/developers/sdk/python/orders#self-trade-prevention), [Rust](/developers/sdk/rust/orders#self-trade-prevention), and [Go](/developers/sdk/go/orders#self-trade-prevention).
**Where does `ownerId` come from?** It is the `id` field returned by [`GET /profiles/me`](/api-reference/portfolio/get-current-profile) or [`GET /profiles/{address}`](/api-reference/portfolio/get-profile). For partner sub-accounts, it is the `profileId` returned by [`POST /profiles/partner-accounts`](/api-reference/partner-accounts/create-partner-account), or recovered with [`GET /profiles/partner-accounts`](/api-reference/partner-accounts/list-partner-accounts).
**`ownerId` must match the profile that owns the order** (see [Programmatic API — EOA flow](/developers/programmatic-api#eoa-web3-partners)):
* **Partner EOA + signed order + `onBehalfOf`:** set both `onBehalfOf` and `ownerId` to the **sub-account’s** `profileId`. `order.maker` and `order.signer` must match that sub-account’s wallet. A mismatched `ownerId` returns `400` — `"Profile ID does not match the order owner"`.
* **Delegated signing** (unsigned `order`, `delegated_signing` scope, server wallet sub-account): the server fills in `ownerId` when it signs — omit the client signature per [Delegated Signing](#delegated-signing) below.
* **Trading as yourself** (no `onBehalfOf`): `ownerId` is your own profile id (the SDK often fills this after fetching your profile).
### Delegated Signing
Partners with the `delegated_signing` scope can omit `signature` and `signatureType` from the order object. The server signs the order using a Privy server wallet linked to the target sub-account and sets `maker`/`signer` to the server wallet address. See [Authentication](/developers/authentication#delegated-signing) for details.
### Execution Response
The response includes an `execution` object with settlement details:
| Field | Type | Description |
| ------------------ | ---------- | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------ |
| `matched` | `boolean` | Whether the order was matched immediately |
| `settlementStatus` | `string` | `UNMATCHED`, `MATCHED`, `MINED`, `CONFIRMED`, `RETRYING`, `FAILED`, `DELAYED`, or `CANCELED` |
| `reason` | `string` | Reason the order was canceled. `STP_TAKER_REJECTED` when self-trade prevention rejected the incoming order (`cancel_taker` / `cancel_both`). Present only when `settlementStatus` is `CANCELED`. |
| `eligibleAt` | `string` | ISO-8601 time the order is released to the matching engine. Present only when `settlementStatus` is `DELAYED` (taker delay). |
| `tradeEventId` | `string` | Trade event ID (present when matched) |
| `txHash` | `string` | On-chain transaction hash (present when mined) |
| `stpMakerCancels` | `string[]` | Resting order IDs canceled by self-trade prevention (present when `cancel_maker` / `cancel_both` cancelled one or more of your resting orders) |
| `feeRateBps` | `number` | Fee rate in basis points |
| `effectiveFeeBps` | `number` | Effective fee rate after rebates |
| `totalsRaw` | `object` | Raw execution totals (`contractsGross`, `contractsFee`, `contractsNet`, `usdGross`, `usdFee`, `usdNet`) |
**`DELAYED` (taker delay).** Some markets apply a short hold to marketable (taker) orders before the matching engine fills them. On such a market, a marketable order's response returns immediately with `settlementStatus: "DELAYED"`, `matched: false`, zero `totalsRaw`, and an `eligibleAt` timestamp — it does **not** block until the trade is mined. Track the outcome over [`subscribe_order_events`](/developers/websocket-events#subscribing-to-order-events) (provisional `MATCHED` → terminal `MINED` / `FAILED`), correlating by `clientOrderId` / `tradeEventId`. `postOnly` orders are never delayed.
## OpenAPI
````yaml POST /orders
openapi: 3.0.0
info:
title: Limitless Exchange API
description: >-
Production-ready REST API for prediction market trading, portfolio
management, and market data on Limitless Exchange (Base L2).
version: '1.0'
contact:
name: API Support
url: https://limitless.exchange
email: help@limitless.network
servers:
- url: https://api.limitless.exchange
description: Production API
security: []
tags:
- name: Authentication
description: User authentication and session management
- name: Markets
description: Browse, search, and analyze prediction markets
- name: Market Navigation
description: Navigation tree, market pages, and property filters
- name: Trading
description: Create, manage, and cancel orders
- name: Portfolio
description: Position tracking, trade history, and performance
- name: API Tokens
description: Scoped API token management for partner integrations
- name: Partner Accounts
description: Sub-account creation and allowance recovery for partner integrations
- name: System
description: Public API state and availability information
paths:
/orders:
post:
tags:
- Trading
summary: Create Order
description: >-
Creates a buy/sell order for prediction market positions. Requires
signed order data.
operationId: OrderController_createOrder
parameters: []
requestBody:
required: true
description: Order creation data including signature and order parameters
content:
application/json:
schema:
$ref: '#/components/schemas/CreateOrderDto'
responses:
'201':
description: Order successfully created and matched
content:
application/json:
schema:
$ref: '#/components/schemas/OrderResponseDto'
'400':
description: >-
Invalid order data, insufficient balance/allowance, or market
deadline passed
content:
application/json:
schema:
$ref: '#/components/schemas/ErrorResponseDto'
'401':
description: User not authenticated
'425':
description: Receive-window check failed. Use a fresh timestamp and submit again.
content:
application/json:
schema:
$ref: '#/components/schemas/ErrorResponseDto'
'500':
description: Server error during order creation
'503':
description: Trading is temporarily limited by maintenance mode
content:
application/json:
schema:
type: object
properties:
code:
type: string
example: cancel_only_mode
message:
type: string
example: >-
Trading is currently cancel-only. New orders are not
accepted, but cancels are allowed.
mode:
type: string
enum:
- post_only
- cancel_only
- disabled
example: cancel_only
resumeAt:
type: string
format: date-time
nullable: true
example: '2026-06-22T18:00:00.000Z'
required:
- code
- message
- mode
examples:
postOnlyMode:
summary: Regular order blocked during post-only mode
value:
code: post_only_mode
message: >-
Trading is currently post-only. Only post-only orders and
cancels are allowed.
mode: post_only
resumeAt: '2026-06-22T18:00:00.000Z'
cancelOnlyMode:
summary: New order blocked during cancel-only mode
value:
code: cancel_only_mode
message: >-
Trading is currently cancel-only. New orders are not
accepted, but cancels are allowed.
mode: cancel_only
resumeAt: '2026-06-22T18:00:00.000Z'
tradingDisabled:
summary: Order creation blocked while trading is disabled
value:
code: trading_disabled
message: Trading is currently disabled.
mode: disabled
resumeAt: '2026-06-22T18:00:00.000Z'
security:
- HmacAuth: []
components:
schemas:
CreateOrderDto:
type: object
properties:
order:
description: Order details including signature and amounts
allOf:
- $ref: '#/components/schemas/Order'
ownerId:
type: number
description: Profile ID of the order owner
example: 12345
orderType:
type: string
description: >-
Order type (GTC=Good Till Cancelled, FAK=Fill And Kill, FOK=Fill Or
Kill)
enum:
- FAK
- FOK
- GTC
example: GTC
marketSlug:
type: string
description: Market identifier slug
example: biden-vs-trump-2024
postOnly:
type: boolean
description: >-
Reject the order if it would match immediately. Supported only for
GTC orders.
example: true
clientOrderId:
type: string
description: >-
Client-provided idempotency key for order placement. If a duplicate
is submitted, the server returns 409 Conflict.
example: client-order-001
maxLength: 128
onBehalfOf:
type: number
description: >-
Profile ID to place order on behalf of (partner flow). Requires an
API token with trading scope and a partner relationship with the
target profile.
example: 12345
timestamp:
type: number
description: >-
Optional client-stamped order creation time, Unix ms epoch.
Top-level request field; not part of the EIP-712 signed order
payload.
example: 1735689600000
minimum: 0
recvWindow:
type: number
description: >-
Optional maximum accepted order age in milliseconds. Valid range: 1
to 10000. If omitted, no receive-window check is applied. Top-level
request field; not part of the EIP-712 signed order payload.
example: 1500
minimum: 1
maximum: 10000
stpPolicy:
type: string
description: >-
Self-trade prevention policy. Top-level request field; not part of
the EIP-712 signed order payload. Defaults to cancel_maker when
omitted.
enum:
- cancel_both
- cancel_maker
- cancel_taker
example: cancel_maker
required:
- order
- ownerId
- orderType
- marketSlug
OrderResponseDto:
type: object
properties:
order:
$ref: '#/components/schemas/CreatedOrderDto'
description: Order details including slim market and owner
makerMatches:
description: Maker matches if order was matched immediately
type: array
items:
$ref: '#/components/schemas/MakerMatch'
execution:
$ref: '#/components/schemas/OrderExecutionDto'
description: Execution and settlement summary
required:
- order
- execution
ErrorResponseDto:
type: object
properties:
message:
type: string
description: Error message
example: Invalid order data
required:
- message
Order:
type: object
properties:
salt:
description: >-
Unique random value for signature uniqueness. Send unsafe integers
as decimal strings to preserve EIP-712 bytes.
oneOf:
- type: string
pattern: ^\d+$
example: '1778155025318314496'
- type: number
example: 1234567890
maker:
type: string
description: Ethereum address of the maker (order creator)
example: '0x742d35Cc6634C0532925a3b844Bc454e4438f44e'
pattern: ^0x[a-fA-F0-9]{40}$
signer:
type: string
description: Address that signed the order
example: '0x742d35Cc6634C0532925a3b844Bc454e4438f44e'
pattern: ^0x[a-fA-F0-9]{40}$
taker:
type: string
description: Specific taker address (optional for open orders)
example: '0x0000000000000000000000000000000000000000'
pattern: ^0x[a-fA-F0-9]{40}$
tokenId:
type: string
description: Token ID being traded (YES or NO position ID from conditional token)
example: >-
19633204485790857949828516737993423758628930235371629943999544859324645414627
makerAmount:
type: number
description: >-
Amount the maker is offering, scaled by 1e6. For GTC orders: price *
size * 1e6 (BUY) or size * 1e6 (SELL). For FOK orders: USDC to spend
* 1e6 (BUY) or shares to sell * 1e6 (SELL).
example: 5000000
minimum: 0
takerAmount:
type: number
description: >-
Amount the maker wants in return, scaled by 1e6. For GTC orders:
size * 1e6 (BUY) or price * size * 1e6 (SELL). For FOK orders:
always 1.
example: 10000000
minimum: 0
expiration:
type: string
description: >-
Order expiration. Must be "0". Non-zero expiration is not currently
supported and orders signed with a non-zero value are rejected.
example: '0'
nonce:
type: number
description: >-
Must be 0. Non-zero nonce is not currently supported and is
rejected.
example: 0
price:
type: number
description: >-
Order price as decimal (0.01-0.99, required for limit-like GTC/FAK
orders)
example: 0.75
minimum: 0.01
maximum: 0.99
feeRateBps:
type: number
description: Fee rate in basis points (1% = 100)
example: 0
side:
type: number
description: 'Order side: 0 = BUY, 1 = SELL'
enum:
- 0
- 1
example: 0
signature:
type: string
description: >-
EIP-712 signature of order details as a 0x-prefixed hex string with
full-byte (even) length. Optional when using delegated signing.
pattern: ^0x([a-fA-F0-9]{2})*$
example: >-
0x123abc456def789ghi0123abc456def789ghi0123abc456def789ghi0123456789012345678901
signatureType:
type: number
description: Signature type (0-3). Optional when using delegated signing.
enum:
- 0
- 1
- 2
- 3
example: 2
required:
- salt
- maker
- signer
- tokenId
- makerAmount
- takerAmount
- feeRateBps
- side
- signature
- signatureType
CreatedOrderDto:
type: object
description: >-
Created order as returned by the API. Large numeric fields (`salt`,
`makerAmount`, `takerAmount`, `nonce`, `price`) are serialized as
decimal strings to preserve precision.
properties:
id:
type: string
format: uuid
description: Internal order ID
salt:
type: string
description: Order salt as decimal string
example: '1778155025318314496'
maker:
type: string
example: '0x742d35Cc6634C0532925a3b844Bc454e4438f44e'
signer:
type: string
example: '0x742d35Cc6634C0532925a3b844Bc454e4438f44e'
taker:
type: string
nullable: true
example: '0x0000000000000000000000000000000000000000'
tokenId:
type: string
example: >-
19633204485790857949828516737993423758628930235371629943999544859324645414627
makerAmount:
type: string
description: Maker amount as decimal string (scaled by 1e6)
example: '5000000'
takerAmount:
type: string
description: Taker amount as decimal string (scaled by 1e6)
example: '10000000'
expiration:
type: string
nullable: true
description: Always "0". Non-zero expiration is not currently supported.
example: '0'
signatureType:
type: integer
enum:
- 0
- 1
- 2
- 3
example: 2
nonce:
type: string
nullable: true
description: Always "0". Non-zero nonce is not currently supported.
example: '0'
feeRateBps:
type: integer
nullable: true
example: 0
signature:
type: string
pattern: ^0x([a-fA-F0-9]{2})*$
orderType:
type: string
enum:
- GTC
- FAK
- FOK
example: GTC
price:
type: string
nullable: true
description: Order price as decimal string (0.01-0.99)
example: '0.75'
side:
type: integer
enum:
- 0
- 1
description: 0 = BUY, 1 = SELL
example: 0
marketId:
type: string
description: Internal market identifier
ownerId:
type: integer
description: Profile ID of the order owner
example: 12345
createdAt:
type: string
format: date-time
updatedAt:
type: string
format: date-time
market:
type: object
description: Slim market info
properties:
id:
type: integer
example: 7348
slug:
type: string
example: btc-up-or-down-1-hour
title:
type: string
example: BTC Up or Down - Hourly
status:
type: string
enum:
- FUNDED
- RESOLVED
- LOCKED
- DRAFT
- FUNDED_FLAGGED
yesPositionId:
type: string
nullable: true
noPositionId:
type: string
nullable: true
group:
type: object
nullable: true
properties:
id:
type: integer
slug:
type: string
title:
type: string
owner:
type: object
nullable: true
description: Public profile of the order owner
properties:
id:
type: integer
account:
type: string
description: Checksummed wallet address
displayName:
type: string
nullable: true
username:
type: string
nullable: true
imageURI:
type: string
nullable: true
required:
- id
- salt
- maker
- signer
- tokenId
- makerAmount
- takerAmount
- signatureType
- signature
- orderType
- side
- marketId
- ownerId
- createdAt
- market
MakerMatch:
type: object
properties: {}
OrderExecutionDto:
type: object
description: Execution and settlement summary for a created order
properties:
matched:
type: boolean
description: Whether the order was matched immediately
example: true
settlementStatus:
type: string
description: >-
Current settlement status of the order. DELAYED means the order was
accepted but is held by a per-market taker delay before being
released to the matching engine. CANCELED with reason
STP_TAKER_REJECTED means self-trade prevention (cancel_taker /
cancel_both) rejected the incoming order.
enum:
- UNMATCHED
- MATCHED
- MINED
- CONFIRMED
- RETRYING
- FAILED
- DELAYED
- CANCELED
example: MINED
reason:
type: string
nullable: true
description: >-
Reason the order was canceled. STP_TAKER_REJECTED when self-trade
prevention rejected the incoming order. Present only when
settlementStatus is CANCELED.
enum:
- STP_TAKER_REJECTED
example: STP_TAKER_REJECTED
eligibleAt:
type: string
format: date-time
nullable: true
description: >-
ISO-8601 time a delayed (taker-delay) order is released to the
matching engine. Present only when settlementStatus is DELAYED.
example: '2026-06-08T10:15:30.000Z'
tradeEventId:
type: string
description: Trade event ID (present when matched)
example: 4aa706dd-6c57-4f3c-945a-99818dfd95f1
txHash:
type: string
description: On-chain transaction hash (present when mined)
example: '0xabc123'
nullable: true
clientOrderId:
type: string
description: Echo of client-provided idempotency key
example: client-order-001
stpMakerCancels:
type: array
description: >-
Resting order IDs canceled by self-trade prevention (cancel_maker /
cancel_both)
items:
type: string
example:
- 4aa706dd-6c57-4f3c-945a-99818dfd95f1
feeRateBps:
type: number
description: Fee rate in basis points applied to this order
example: 25
effectiveFeeBps:
type: number
description: Effective fee rate in basis points after any rebates
example: 26
totalsRaw:
$ref: '#/components/schemas/OrderExecutionTotalsRawDto'
required:
- matched
- settlementStatus
- feeRateBps
- effectiveFeeBps
- totalsRaw
OrderExecutionTotalsRawDto:
type: object
description: Raw execution totals in contract units (strings to preserve precision)
properties:
contractsGross:
type: string
example: '1000000'
contractsFee:
type: string
example: '1000'
contractsNet:
type: string
example: '999000'
usdGross:
type: string
example: '500000'
usdFee:
type: string
example: '500'
usdNet:
type: string
example: '499500'
required:
- contractsGross
- contractsFee
- contractsNet
- usdGross
- usdFee
- usdNet
securitySchemes:
HmacAuth:
type: apiKey
in: header
name: lmts-api-key
description: >-
Scoped API token with HMAC-SHA256 signing. Requires three headers:
lmts-api-key (token ID), lmts-timestamp (ISO-8601), lmts-signature
(Base64-encoded HMAC). See Authentication docs for details.
````