POST Replace Order

NT8

Cancel & replace an existing order by ID NT8

Cancels one working order and submits its replacement as a single API workflow.

Endpoint

POST /v1/api/accounts/{account}/orders/{orderId}/replace

Headers

Name	Value
Content-Type	application/json
Authorization	Bearer <token>

Path parameters

Name	Type	Required	Description
account	string	Required	Name of account in NT8
orderId	string	Required	ID of the order to by replaced

Body parameters

Name	Type	Required	Description
instrument	string	Optional	Replacement instrument. Defaults to the existing order's instrument and cannot move the order to a different instrument.
action	string	Optional	BUY or SELL. Defaults to the existing order action.
quantity	int	Optional	Replacement contract quantity. Defaults to the existing order quantity.
orderType	string	Optional	MARKET, LIMIT, STOPMARKET, or STOPLIMIT. Defaults to the existing order type.
timeInForce	string	Optional	DAY or GTC. Defaults to the existing order time in force.
limitPrice	float	Optional	Replacement limit price. Defaults to the existing limit price when required by its order type.
stopPrice	float	Optional	Replacement stop price. Defaults to the existing stop price when required by its order type.
ocoId	string	Optional	Create or append to OCO order by ID.
strategy	string	Optional	ATM strategy name if opening with an ATM template.

Code examples

Python

import requests

token = 'my-secret-token'

url = "https://app.crosstrade.io/v1/api/accounts/Sim101/orders/fba1e883dbd241308814d2d1f5687ace/replace"
headers = {
    "Authorization": f"Bearer {token}",
    "Content-Type": "application/json"
}
data = {
    "instrument": "MES 12-25",
    "action": "BUY",
    "orderType": "LIMIT",
    "quantity": 1,
    "timeInForce": "DAY",
    "limitPrice": 6000
    # "stopPrice": 0,
    # "ocoId": "abc123",
    # "strategy": "MyAtmStrategy"
}

try:
    response = requests.post(url, headers=headers, json=data)
    print(f"Response Code: {response.status_code}, Response Text: {response.text}")
except Exception as e:
    print(f"An error occurred: {e}")

JavaScript

const token = 'my-secret-token';

const url = "https://app.crosstrade.io/v1/api/accounts/Sim101/orders/fba1e883dbd241308814d2d1f5687ace/replace";
const data = {
  instrument: "MES 12-25",
  action: "BUY",
  orderType: "LIMIT",
  quantity: 1,
  timeInForce: "DAY",
  limitPrice: 6000
  // stopPrice: 0,
  // ocoId: "abc123",
  // strategy: "MyAtmStrategy"
};

fetch(url, {
  method: "POST",
  headers: {
    "Authorization": `Bearer ${token}`,
    "Content-Type": "application/json"
  },
  body: JSON.stringify(data)
})
  .then(res => res.json())
  .then(data => console.log(data))
  .catch(err => console.error(err));

cURL

TOKEN="my-secret-token"

curl -X POST "https://app.crosstrade.io/v1/api/accounts/Sim101/orders/fba1e883dbd241308814d2d1f5687ace/replace" \
  -H "Authorization: Bearer $TOKEN" \
  -H "Content-Type: application/json" \
  -d '{
    "instrument": "MES 12-25",
    "action": "BUY",
    "orderType": "LIMIT",
    "quantity": 1,
    "timeInForce": "DAY",
    "limitPrice": 6000
  }'

Response

200

{
    "orderId": "36f59a2f4594436084484b92350ca25a",
    "success": true
}

400

{
  "error": "Invalid request"
}

Platform nuances

• Only account and orderId are required. Omitted instrument, action, order type, quantity, time in force, and applicable price fields are restored from the existing order.
• A replacement cannot move the order to another instrument.
• The add-on waits up to 4.5 seconds for the original order and mapped Trade Copier follower orders to finish cancelling. The replacement is placed only when those orders finish in the Cancelled state.

WebSocket API

This request can also be made over the WebSocket API. The account and orderId path parameters and request body fields are all passed inside args.

{
  "action": "rpc",
  "id": "my-request-id",
  "api": "CancelReplace",
  "args": {
    "account": "Sim101",
    "orderId": "492281fc515e431692da57d957cfebb6",
    "instrument": "ES 09-26",
    "action": "Buy",
    "orderType": "Limit",
    "quantity": 2,
    "limitPrice": 5400.00,
    "timeInForce": "Gtc"
  }
}

Tradovate

Cancel & replace an existing order by ID Tradovate

Cancels one working Tradovate order and submits its replacement as one durable, owner-fenced workflow. No NinjaTrader add-on is involved: the command runs server-side with the same validation, Account Manager locks, and Trade Copier fan-out as a webhook signal.

Endpoint

POST /v1/api/tv/accounts/{account}/orders/{id}/replace

Headers

Name	Value
Content-Type	application/json
Authorization	Bearer <token>

Path parameters

Name	Type	Required	Description
account	string	Required	Tradovate account name, for example DEMO12345678.
id	string	Required	Tradovate order id or an orderId assigned on an earlier place call.

Body parameters

Name	Type	Required	Description
instrument	string	Required	Continuous (ES1!), NT8 (ES 09-26), or Tradovate (ESU6) instrument form.
action	string	Required	buy or sell for the replacement.
qty	int	Required	Replacement contract quantity.
orderType	string	Required	Replacement order type.
limitPrice	number	Optional	Replacement limit price.
stopPrice	number	Optional	Replacement stop price.
tif	string	Optional	Replacement time in force.
text	string	Optional	Free-form replacement order note. Truncated to 64 characters (Tradovate's limit).
expireTime	string	Optional	ISO-8601 expiry; required when tif=gtd.
maxShow	int	Optional	Native iceberg display quantity.
trailOffset	number	Optional	Native trailing-stop distance. Required for trailing order types.
pegDifference	number	Optional	Alias of trailOffset.
requireMarketPosition	string	Optional	Gate the operation on flat, long, or short.
maxPositions	int	Optional	Block the replacement when this many positions are already open.
cancelAfter	int	Optional	Cancel an unfilled replacement limit order after 1 to 180 minutes.
syncStrategy	bool	Optional	Enable Tradovate Strategy Sync for this entry command.
marketPosition	string	Optional	Remote strategy target side: flat, long, or short.
prevMarketPosition	string	Optional	Remote strategy side before this signal.
outOfSync	string	Optional	Mismatch policy: wait, flatten, ignore, or resync.
targetQuantity	int	Optional	Exact signed target quantity for resync mode.
strategyExitBlock	bool	Optional	Reject non-opening strategy transitions.

Code examples

Python

import requests

token = 'my-secret-token'

url = "https://app.crosstrade.io/v1/api/tv/accounts/DEMO12345678/orders/123456789/replace"
headers = {
    "Authorization": f"Bearer {token}",
    "Content-Type": "application/json"
}
data = {
    "instrument": "ES1!",
    "action": "buy",
    "qty": 1,
    "orderType": "limit",
    "limitPrice": 5400.00
}

try:
    response = requests.post(url, headers=headers, json=data)
    print(f"Response Code: {response.status_code}, Response Text: {response.text}")
except Exception as e:
    print(f"An error occurred: {e}")

JavaScript

const token = 'my-secret-token';

const url = "https://app.crosstrade.io/v1/api/tv/accounts/DEMO12345678/orders/123456789/replace";
const data = {
  instrument: "ES1!",
  action: "buy",
  qty: 1,
  orderType: "limit",
  limitPrice: 5400.00
};

fetch(url, {
  method: "POST",
  headers: {
    "Authorization": `Bearer ${token}`,
    "Content-Type": "application/json"
  },
  body: JSON.stringify(data)
})
  .then(res => res.json())
  .then(data => console.log(data))
  .catch(err => console.error(err));

cURL

TOKEN="my-secret-token"

curl -X POST "https://app.crosstrade.io/v1/api/tv/accounts/DEMO12345678/orders/123456789/replace" \
  -H "Authorization: Bearer $TOKEN" \
  -H "Content-Type: application/json" \
  -d '{"instrument": "ES1!", "action": "buy", "qty": 1, "orderType": "limit", "limitPrice": 5400.00}'

Response

The response is the response envelope with api set to cancel_replace.

{
  "success": true,
  "destination": "tradovate",
  "api": "cancel_replace",
  "account": "DEMO12345678",
  "instrument": "ES1!",
  "response": {},
  "durationMs": 214
}

Platform nuances

• Tradovate uses {id} in the path where NT8 uses {orderId}. The body fields use the same camelCase keys as the NT8 surface.
• Concurrent operations on the same original order are serialized, and staged recovery state is persisted before each broker mutation.
• The original order must belong to the {account} in the path, and the replacement instrument must resolve to the same exact contract.
• CrossTrade confirms the leader cancellation and every mapped Trade Copier follower cancellation before replacement fan-out.
• If a cancel or placement result is ambiguous, CrossTrade does not resend it. It returns reconciliation_required; reconcile broker orders before starting another replacement.
• Account Manager locks apply. On failure, the response is {"success": false, "error": "<message>"}.

See the Tradovate API overview for the full field grammar, mutation safety guarantees, and error table.