https://developer.themoviedb.org/reference/credit-details

The credit can be included in the movie & tv response

Is the credit_id a one-to-one to every tv show and movie? the credit_id string, not id

it is hard to say, but it looks like it is tied to the character in one production appearance, and not the actor or crew member

if the same character appears in multiple episodes and movies, can you please confirm that they have unique credit_id?

I think tv shows, seasons & episodes have their own credits section, you also clarify if their credit_ids / ids overlap or not?

Thank you