Cancel and Replace Order

POST /orders/cancel-replace

Cancel an order and place a replacement non-atomically

cURL

curl --request POST \
  --url https://api.limitless.exchange/orders/cancel-replace \
  --header 'Content-Type: application/json' \
  --header 'lmts-api-key: <api-key>' \
  --data '
{
  "cancel": {
    "orderId": "6f52b6d2-6c9e-4a5c-8a4f-28ab4b7ff203",
    "clientOrderId": "partner-order-001"
  },
  "replacement": {
    "order": {
      "salt": "1778155025318314496",
      "maker": "0x742d35Cc6634C0532925a3b844Bc454e4438f44e",
      "signer": "0x742d35Cc6634C0532925a3b844Bc454e4438f44e",
      "tokenId": "19633204485790857949828516737993423758628930235371629943999544859324645414627",
      "makerAmount": 5000000,
      "takerAmount": 10000000,
      "nonce": 0,
      "feeRateBps": 0,
      "side": 0,
      "signature": "0x6e3a3f2c2c2bb1ce3a14c4f5e4ad6f3c8b1ad9c44d4d5fa1c4cd5b6e74a4d4a36cc4ad9c44d4d5fa1c4cd5b6e74a4d4a36cc4ad9c44d4d5fa1c4cd5b6e74a4d41b",
      "signatureType": 2,
      "taker": "0x0000000000000000000000000000000000000000",
      "expiration": "0",
      "price": 0.75
    },
    "ownerId": 12345,
    "orderType": "GTC",
    "marketSlug": "biden-vs-trump-2024",
    "postOnly": true,
    "clientOrderId": "client-order-001",
    "timestamp": 1735689600000,
    "recvWindow": 1500,
    "stpPolicy": "cancel_maker"
  },
  "mode": "STOP_ON_FAILURE",
  "onBehalfOf": 12345
}
'

200

{
  "cancel": {
    "status": "SUCCESS",
    "orderId": "3c90c3cc-0d44-4b50-8888-8dd25736052a",
    "clientOrderId": "<string>"
  },
  "replacement": {
    "status": "SUCCESS",
    "data": {
      "order": {
        "id": "3c90c3cc-0d44-4b50-8888-8dd25736052a",
        "salt": "1778155025318314496",
        "maker": "<string>",
        "signer": "<string>",
        "tokenId": "<string>",
        "signatureType": 0,
        "signature": "<string>",
        "orderType": "GTC",
        "side": 0,
        "marketId": "<string>",
        "ownerId": 123,
        "createdAt": "2023-11-07T05:31:56Z",
        "market": {
          "id": 7348,
          "slug": "btc-up-or-down-1-hour",
          "title": "BTC Up or Down - Hourly",
          "status": "FUNDED",
          "yesPositionId": "11514974713064423461...",
          "noPositionId": "14525308260861904048...",
          "group": {
            "id": 42,
            "slug": "btc-price-markets",
            "title": "BTC Price Markets"
          }
        },
        "makerAmount": 5000000,
        "takerAmount": 10000000,
        "nonce": 0,
        "owner": {
          "id": 123,
          "account": "<string>",
          "client": "<string>",
          "tradeWalletOption": "eoa",
          "smartWallet": "<string>",
          "username": "<string>",
          "displayName": "<string>",
          "pfpUrl": "<string>",
          "socialUrl": "<string>",
          "rankName": "<string>",
          "points": 123,
          "referredUsersCount": 123,
          "isTop100": true,
          "leaderboardPosition": 123
        },
        "taker": "<string>",
        "expiration": "2023-11-07T05:31:56Z",
        "feeRateBps": 123,
        "price": 0.75
      },
      "execution": {
        "matched": true,
        "settlementStatus": "MINED",
        "feeRateBps": 25,
        "effectiveFeeBps": 26,
        "totalsRaw": {
          "contractsGross": "1000000",
          "contractsFee": "1000",
          "contractsNet": "999000",
          "usdGross": "500000",
          "usdFee": "500",
          "usdNet": "499500"
        },
        "reason": "settlement transaction reverted",
        "eligibleAt": "2026-06-08T10:15:30.000Z",
        "tradeEventId": "4aa706dd-6c57-4f3c-945a-99818dfd95f1",
        "txHash": "0xabc123",
        "clientOrderId": "client-order-001",
        "stpMakerCancels": [
          "4aa706dd-6c57-4f3c-945a-99818dfd95f1"
        ]
      },
      "makerMatches": [
        {
          "id": "3c90c3cc-0d44-4b50-8888-8dd25736052a",
          "matchedSize": "1000000",
          "fillPrice": "0.55",
          "fillCost": "550000",
          "orderId": "3c90c3cc-0d44-4b50-8888-8dd25736052a",
          "order": {
            "id": "3c90c3cc-0d44-4b50-8888-8dd25736052a",
            "maker": "<string>",
            "price": "0.55",
            "side": 0,
            "tokenId": "<string>",
            "owner": {
              "id": 123,
              "account": "<string>",
              "client": "<string>",
              "tradeWalletOption": "eoa",
              "smartWallet": "<string>",
              "username": "<string>",
              "displayName": "<string>",
              "pfpUrl": "<string>",
              "socialUrl": "<string>",
              "points": 0,
              "referredUsersCount": 0
            }
          }
        }
      ]
    }
  }
}

Cancel one order and submit its replacement in one request. The two actions are not atomic: cancellation and replacement have independent outcomes, and a successful cancellation does not guarantee a successful replacement.

Request

Field	Type	Description
cancel	object	Identifies the order to cancel. Provide exactly one of orderId or clientOrderId.
replacement	object	A standard signed order request. It accepts the same fields as POST /orders, except onBehalfOf.
mode	string	STOP_ON_FAILURE or ALLOW_FAILURE. Controls whether replacement is attempted after cancellation fails.
onBehalfOf	number	Optional profile ID for an authorized partner sub-account. Applies to both cancellation and replacement.

replacement.ownerId must own the order being cancelled. Put onBehalfOf only at the operation level, not inside replacement. The x-on-behalf-of header is not supported by this endpoint.

Failure modes

Mode	Cancellation fails	Replacement result
STOP_ON_FAILURE	Stops this operation	NOT_ATTEMPTED
ALLOW_FAILURE	Continues this operation	Placement is attempted and reports SUCCESS, FAILURE, or UNKNOWN independently

Authentication and signing

Use a scoped API token with the trading scope and HMAC-sign the exact request body and path /orders/cancel-replace; see Authentication.

The cancellation itself is not EIP-712 signed. For a direct request, the replacement is a normal order and must contain an EIP-712 signature. The authenticated profile must be a valid signer of the order being cancelled.

For an authorized partner sub-account, set the operation-level onBehalfOf to the sub-account profile ID and set replacement.ownerId to the same ID. This path requires delegated_signing in addition to trading. If the replacement omits its order signature, the server signs it only for a managed server-wallet sub-account under the existing delegated signing rules.

Example: stop after cancellation failure

The order values below illustrate the request shape. Generate order.signature from the complete replacement payload instead of copying the placeholder signature.

{
  "cancel": {
    "clientOrderId": "old-order-001"
  },
  "replacement": {
    "ownerId": 12345,
    "orderType": "GTC",
    "marketSlug": "btc-100k",
    "clientOrderId": "replacement-001",
    "order": {
      "salt": "1778155025318314496",
      "maker": "0x742d35Cc6634C0532925a3b844Bc454e4438f44e",
      "signer": "0x742d35Cc6634C0532925a3b844Bc454e4438f44e",
      "taker": "0x0000000000000000000000000000000000000000",
      "tokenId": "19633204485790857949828516737993423758628930235371629943999544859324645414627",
      "makerAmount": 5000000,
      "takerAmount": 10000000,
      "nonce": 0,
      "price": 0.5,
      "feeRateBps": 0,
      "side": 0,
      "signature": "0x1234",
      "signatureType": 0
    }
  },
  "mode": "STOP_ON_FAILURE"
}

If old-order-001 is not found, the response is 409 Conflict:

{
  "cancel": {
    "status": "FAILURE",
    "error": {
      "code": "ORDER_NOT_FOUND",
      "message": "Order not found"
    }
  },
  "replacement": {
    "status": "NOT_ATTEMPTED"
  }
}

Example: allow replacement after cancellation failure

Changing mode to ALLOW_FAILURE attempts the replacement even if cancellation fails. The replacement reports its own result. The response remains 409 Conflict because the complete cancel-and-replace operation did not succeed:

{
  "cancel": {
    "status": "FAILURE",
    "error": {
      "code": "ORDER_NOT_FOUND",
      "message": "Order not found"
    }
  },
  "replacement": {
    "status": "FAILURE",
    "error": {
      "code": "400",
      "message": "Insufficient balance"
    }
  }
}

Validation and outcomes

Request-level authentication, authorization, validation, market, signature, maintenance-mode, and receive-window failures return their ordinary HTTP status without a cancel/replace result. Maintenance-mode and receive-window rejections use 425 Too Early.

A successful cancellation does not guarantee replacement success. Insufficient balance or allowance can produce cancel.status: "SUCCESS" with replacement.status: "FAILURE" and an HTTP-status error code such as "400"; the endpoint returns 409 Conflict.

A receive-window or trading-availability rejection can likewise produce a successful cancellation with replacement.status: "FAILURE" and error.code: "425".

{
  "cancel": {
    "status": "SUCCESS",
    "orderId": "6f52b6d2-6c9e-4a5c-8a4f-28ab4b7ff203"
  },
  "replacement": {
    "status": "FAILURE",
    "error": {
      "code": "425",
      "message": "order receive window expired: elapsed=2500ms, window=1500ms"
    }
  }
}

Response semantics

cancel.status can be SUCCESS, FAILURE, or UNKNOWN. replacement.status can be SUCCESS, FAILURE, UNKNOWN, or NOT_ATTEMPTED.

Outcome	HTTP status
Cancellation and replacement are both SUCCESS	200 OK
Cancellation fails under STOP_ON_FAILURE; replacement is NOT_ATTEMPTED	409 Conflict
Cancellation fails under ALLOW_FAILURE; replacement is attempted	409 Conflict
The service returns any other non-success top-level result	409 Conflict

Operation error codes are strings, not a closed enum. A missing cancellation target uses ORDER_NOT_FOUND; request failures use their decimal HTTP status such as 400, 404, 409, 425, or 500; other failures use INTERNAL_ERROR. FAILURE identifies a known failure and UNKNOWN an inconclusive outcome. Cancellation authorization failures remain request-level 401 or 403 responses.

replacement.status: "SUCCESS" means the placement was accepted. It does not guarantee on-chain settlement. A matched replacement remains top-level SUCCESS when replacement.data.execution.settlementStatus is FAILED; the settlement failure and reason remain nested under execution. There is no top-level SETTLEMENT_FAILED replacement status.

Authorizations

lmts-api-key · string · header · required

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.

Body

application/json

cancel · object · required

Order to cancel; provide exactly one identifier

Option 1

Option 2

Show child attributes

replacement · object · required

Replacement order fields. This is the POST /orders request shape without onBehalfOf; delegation is set on the enclosing cancel-replace operation.

Show child attributes

mode · enum<string> · required

Whether to stop this operation or attempt replacement after cancellation failure

Available options: ALLOW_FAILURE, STOP_ON_FAILURE

Example:

"STOP_ON_FAILURE"

onBehalfOf · number

Authorized partner sub-account profile ID. Applies to both cancellation and replacement.

Required range: x >= 1

Example:

12345

Response

200

application/json

Cancellation and replacement both succeeded

Independent cancellation and replacement outcomes.

cancel · object · required

Option 1

Option 2

Show child attributes

replacement · object · required

The matching engine accepted the replacement. The canonical created-order, owner, maker-match, and execution schemas are reused; nested settlementStatus may still be FAILED with a free-form reason.

Option 1

Option 2

Option 3

Show child attributes