I use scope=write_orders in oauth/authorize, yet later on when I try to create a webhook for fulfillments/create I get this error:
You do not have permission to create webhooks with fulfillments/create topic
I believe you also need permission for fulfillments_read or fulfillments_write depending on your use case. I couldn't find backing documentation for this.
Are you looking to pick up on when an order is fulfilled? If that's the case you need to subscribe to the orders/fulfilled and orders/partially_fulfilled webhooks which don't require extra permissions than those you already have.
First of all, you were right the 1st answer. I added write_fulfillment and it worked...
However, you are even more right on the 2nd answer. I *am* looking to be notified on orders fulfillments and I missed those webhooks you suggested. So I'll switch to them. Thanks!