Hey. I would like to know if there is a way for me to be able to send some information based on the url login is called from (using custom U.I.), to my backend so I can assign some role to a user based on that information.

Hi

I was looking into a method to pass a specific header in the signinup request

Just so I understand correctly, the same API endpoint is called from two different domains?

Yes

Which recipe are you using?

thirdpartypasswordless

Right so you use our override feature to get access to custom headers and body properties for the API (https://supertokens.com/docs/thirdpartypasswordless/advanced-customizations/apis-override/usage) And then use our user context feature to set custom information when calling the original implementation (https://supertokens.com/docs/thirdpartypasswordless/advanced-customizations/user-context)

ok, thanks