CarrierService - Why I am not receiving shipping data at callback url

Retired Boards Appdev Custom Storefronts

Topic summary

A developer is troubleshooting a CarrierService integration for custom shipping rates on their development store. The issue: while Shopify successfully calls the callback URL during checkout, it’s not sending essential shipping data (zip code and item weight) needed to calculate rates from their logistics provider.

Current Setup:

  • Private app created for custom shipping rates
  • CarrierService configured with callback URL
  • Service discovery and active flags enabled

Problem:
The callback receives requests but lacks critical shipping parameters, preventing rate calculation.

Status:
The developer is seeking guidance on what configuration or implementation step might be missing to ensure shipping data is properly transmitted to the callback endpoint.

Summarized with AI on November 20. AI used: claude-sonnet-4-5-20250929.
1

I have a development store and created a private app to get custom shipping rates from a logistics company.

At the time of checkout, the system successfully hits the callback URL but it does not send any shipping information to Callback URL. Without zip code and item weight shipping rates can’t be calculated.

What I am missing here, please help.

Development Store: https://mwbddeveloper.myshopify.com/

CarrierService created:

{
“carrier_service”: {
“id”: 74661757204,
“name”: “Pricing App V 2.2”,
“active”: true,
“service_discovery”: true,
“carrier_service_type”: “api”,
“admin_graphql_api_id”: “gid://shopify/DeliveryCarrierService/74661757204”,
“format”: “json”,
“callback_url”: “https://7ee7-182-191-84-202.ngrok-free.app/CS/COut”
}
}