Passing an API Key to Frends API from a client

An API Key can be passed in the request headers specified in API specification or in query parameters.

In version 5.3.3 and before, the API Key must be passed either within the Authorization header using the ApiKey type or with the X-ApiKey

For example:
​Authorization:ApiKey 12345678-1234-1234-1234-1234567890ab
or:
​X-ApiKey: 12345678-1234-1234-1234-1234567890ab

The next article is Introduction to Rulesets