How do I call AWS Cognito APIs?

Hey there!

I'm trying to set us up so that we can run some actions against AWS Cognito. I've tried configuring a REST resource with a base URL of https://cognito-idp.eu-west-1.amazonaws.com, and set authentication to be AWS v4 with region eu-west-1 and Access Keys with correct permissions.

However, I'm unable to figure out how to make a request to e.g the AWSCognitoIdentityProviderService.AdminGetUser endpoint. Any pointers?