Delivery instructions are notes for the driver, such as "Leave at the back door" or a gate code. SKULabs shows them on the order and in the ship window, and sends them to carriers that accept delivery notes when you buy the label.
Where delivery instructions come from
Shopify cart: a cart note attribute named delivery_instructions imports as the order's delivery instructions instead of a regular note.
Shopify order metafield: an order metafield with the key delivery_instructions imports as delivery instructions too, if its namespace is listed in the store's Import metafields with the following namespaces setting. See Shopify order metafields in SKULabs.
Added in SKULabs: you can add one internal delivery instruction to any order.
How to add delivery instructions to an order
Open the order.
In the Delivery Instructions section under the notes, add a manual delivery instruction.
Enter the Note and click Save. To delete it later, open it and click Remove.
The ship window shows the order's delivery instructions, so the shipper can check them before buying the label. Packing slip templates can print them with the deliveryInstructions variable.
Which carriers receive delivery instructions
When an order has delivery instructions, SKULabs joins them into one note and sends it with the label request to:
FedEx connected directly: as the recipient's delivery instructions.
Carriers through EasyPost: as handling instructions. Whether they print on the label depends on the carrier.
OnTrac and FedEx through Shippo: up to 500 characters.
Amazon Buy Shipping: as delivery notes, up to 256 characters.
Other carriers, including UPS connected directly, don't receive the note. Write the instructions on the package if the driver must see them.