To Billit

Below you can find all accepted header values that have a usage with the API

Header Name	Header Value	Header Usage
PartyID	INT - A party ID	To define the context, the ID of your company. When you use multiple companies, then make sure that in the header of your API the correct company is addressed.
ContextPartyID	INT - A party ID	To combine when you are using application as an accountant
ApiKey	"Secret ID'	To be authenticated with the API
Authorization	"Access token"	To be authenticated with the API
Idempotent-Key	"Unique client generated string"	To make unique requests
StrictTransportType	"true"	To make transportTypes strict (no fallback to alternative method if the primary method is not available)

From Billit

Header Name	Header Value	Header Usage
Billit-Signature	String (Time +Encrypted)	To verify the webhook