Trax (SONIC) and Shopify, with charges pushed per parcel

What the Trax integration does

• Books from the Shopify order on Trax's Regular service, in Rush or Saver Plus mode. COD orders go as COD; prepaid orders go with nothing to collect.
• Puts your store on the air waybill. Bookings ask Trax to print the merchant's contact details, because customers expect the shop's name on the parcel, not the courier's.
• Prints Trax's own air waybill, the same CN the SONIC portal produces, one PDF for the whole batch.
• Cancels a booking from the same screen.
• Receives status by webhook. Trax pushes each status change to Kaarobar as it happens, so you don't wait for a polling cycle.
• Sends NDR decisions to Trax. Re-attempt or return from the NDR worklist becomes a SONIC intercept request: Re-Attempt Request or Return Confirm. Trax requires the address and phone on every such request, and Kaarobar fills them in from the original booking.
• Records COD settlement and charges per parcel. More on that below.

Setup: the fields Trax insists on

A Shopify COD order is missing several things Trax won't book without. You enter them once on Kaarobar's Connect page:

1. API key. In the SONIC portal, click your company name at the top right and open your profile. The API key is on the bottom row.
2. Booking email. Trax rejects any shipment without a consignee email, and COD customers often don't give one, so one contact email is used for all your bookings. This was the field that blocked the first real Trax booking, so Kaarobar asks for it up front.
3. Pickup address. Leave it blank if your Trax account has one; Kaarobar finds it. With several, you pick from the list Trax returns. You can change it, or the email, later without reconnecting.
4. Charges mode. Reimbursement (charges deducted from your COD, the usual COD account) or Corporate Invoicing (charges billed to you separately).
5. Shipping mode and product type. Rush or Saver Plus, and a product category such as apparel, cosmetics or footwear.

After saving, Kaarobar gives you a webhook URL to paste into SONIC's subscriptions. It carries delivery status, payment status and charges, so don't skip it.

Trax's quirks, handled

• Cities are numbers. Trax books by city ID, not city name, and only for cities on your account's service. Kaarobar keeps your account's city list and maps the order's city to Trax's ID. If a city can't be found, the error names your city so you can map it on the Couriers screen.
• Weight is mandatory. Trax won't book without a weight. Kaarobar sends the parcel weight when it has one and half a kilo otherwise, a common floor for apparel. Trax's charges webhook then reports the weight it actually billed.
• Insurance is never switched on for you. It is only valid on accounts authorised for it when they were opened, and a rejected booking costs more than an uninsured parcel.
• The webhook has three seconds. SONIC blocks a subscription after five failed or slow deliveries, and you then have to re-activate it in the portal. Kaarobar's webhook only records the event and answers immediately, then processes it afterwards, so a busy moment never gets you unsubscribed.
• Dates are day-first. SONIC sends DD/MM/YYYY, which a careless parser reads as month-first, turning 7 April into 4 July. Kaarobar reads it the way Trax means it.

Charges and settlement, pushed instead of guessed

This is where Trax is better than most couriers. Its charges webhooks send the full cost of each parcel: weight charge, fuel surcharge, cash-handling fee, packaging, GST and net payable, then return charges once a parcel comes back. Kaarobar keeps return charges separate from delivery charges, so the cost of your RTOs stays visible instead of disappearing into a single freight figure.

COD settlement comes from Trax's payment status. A parcel counts as paid only when Trax reports the money as processed, paid or transferred, never while it's pending or on hold. Your full Trax history is backfilled on connect, so the reconciliation starts with your past parcels as well as new ones.

Trax statuses, as Kaarobar reads them

Trax writes statuses as phrases, such as "Shipment - Delivered" and "Return - Delivered to Shipper". The second one contains the word delivered, but it's a return. A parcel that came back is never counted as a sale, which matters more than anything else in this table:

Those stages are the same ones PostEx parcels land in, so the courier scorecard compares Trax and PostEx on identical definitions, with the parcel count shown next to every rate.

Trax next to PostEx

Trax uses the same booking queue, NDR worklist and profit ledger as PostEx. Booking rules send orders by city, COD amount, payment type or the customer's return history. A rule can also route each city to whichever connected courier has actually delivered best there. A challenger has to beat the current courier by a clear margin before volume moves, so a week of noise doesn't shuffle your parcels between couriers.

Questions merchants actually ask

Is Trax the same as SONIC?

Yes. SONIC is the name of Trax's merchant portal and API. The API key Kaarobar needs is in your SONIC profile.

Why does Kaarobar ask me for an email to connect Trax?

Trax rejects any booking without a consignee email, and most COD customers don't provide one. Kaarobar uses the email you give it on every Trax booking.

Do I have to set up the webhook?

Yes, if you want live status and per-parcel charges. Kaarobar shows the URL after you save your API key; paste it into SONIC's subscriptions. Changing your pickup address or email later doesn't change the URL.

Will my old Trax parcels show up?

Yes. Your Trax history is backfilled when you connect, so delivery rates, RTOs and settlement include parcels booked in the SONIC portal before you installed.

Can I move all my volume to Trax?

You can route as much or as little as you like through booking rules. For most stores the better move is to split by region and let the scorecard decide after a few hundred parcels.

Trax ke charges Kaarobar mein kaise aate hain?

Trax webhook ke zariye har parcel ke charges bhejta hai: weight, fuel, cash handling, GST aur return charges. Kaarobar inhein har order ke saath jod deta hai, is liye profit mein asli courier kharcha shamil hota hai.