Generate Label

Queue label generation for a return. This endpoint triggers an asynchronous label generation process for the specified return.

Required API key scope

• Returns

Retrieving the Generated Label

After the label generation is queued (202 response), the label will be processed asynchronously. Once generation is complete, you can retrieve the label data by calling the Get Return Details endpoint:

GET /warehouse/return/details?return_id={returnId}

The response will include a labels array containing the generated label with:

• url: The link to the shipping label PDF
• tracking_number: The tracking number for the shipment
• carrier: The shipping carrier (e.g., USPS, UPS)
• status: The current status of the label
• rate: The shipping cost

Successful Response

Returns HTTP 202 (Accepted) when the label generation has been successfully queued.

Error Responses

• 404 Not Found (return_not_found): The specified return does not exist
• 409 Conflict (label_already_exists): A label has already been generated for this return
• 422 Unprocessable Entity (return_cannot_receive_label): The return is not in a valid state to receive a label
• 422 Unprocessable Entity (label_generation_failed): A previous label generation attempt failed
• 500 Internal Server Error (internal_error): An unexpected error occurred

POST /returns/{returnId}/labels

Generate Label

cURL

curl --request POST \
  --url https://api.loopreturns.com/api/v1/returns/{returnId}/labels \
  --header 'Authorization: Bearer <token>'

202

{
  "message": "Label generation queued",
  "returnId": 12345
}

Authorizations

oauth2returns

Authorization · string · header · required

The access token received from the authorization server in the OAuth 2.0 flow.

Path Parameters

returnId · integer · required

The unique identifier for the return, created by Loop.

Example:

12345

Response

202

application/json

Label generation queued successfully

message · string · required

Confirmation message that label generation has been queued.

Example:

"Label generation queued"

returnId · integer<int64> · required

The return ID for which label generation was queued.

Example:

12345