Sessions vs Traces?

[Manouchehri]

I'm having a hard time understanding if I should use a session or trace in this example.

1. Call to gpt-4-1106-preview writes an email.
2. Call to gpt-3.5-turbo-1106 formats the email from the previous step.

Would it make sense to bundle these together in a session, or in a single trace?

[Manouchehri]

cc @krrishdholakia

[marcklingen]

If it's a single workflow / user-interaction, most users put it into a single trace.