Start writing Parquet files of the key's mail: one file per inbox, one row per message, with the same fields and rules as /v1/threads (never drafts; subjects, snippets, attachment file names and ids, to-do summaries and full text and HTML bodies only with mail.content.read). Poll GET /v1/exports/{id} until status is succeeded, then download the files. A team runs one export at a time (export_in_progress otherwise). See the guide for the file columns.

Scope: mail.metadata.read. Rate limit class: export (10/hour per key).