Channel to list conversations for. EMAIL is currently the only supported value — SMS/MMS conversations are listed by GET /sms/threads, which models them as a phone-number pair rather than a reply chain.

Filter conversations to one agent. Optional for master keys (omit for every agent in the org); ignored for agent keys, which always see only their own.

Filter conversations to one inbox — the precise way to read a single mailbox.

Only conversations containing a message in this direction. OUTBOUND is a Sent view. Note that the returned counts then describe the MATCHING messages, not the thread's full length.

Include messages classified as spam on arrival. They are excluded by default. Naming spam in labels also counts as asking for it, so a deliberate spam query is never silently emptied by this default.

Include messages carrying the archived label. They are excluded by default, so archiving actually removes mail from a listing rather than only tagging it. Naming archived in labels also counts as asking for it (and returns ONLY archived mail); use this flag instead to see archived mail mixed in with the rest.

How to treat messages moved to Trash. exclude (default) hides them, so deleted mail disappears from every ordinary listing. only returns nothing but Trash. include ignores the distinction. Deletion is reversible — see DELETE /messages/{id} and POST /messages/{id}/restore.

Maximum conversations to return per page (1–100, default 20)

Conversations to skip, for paging through the list