Errors › 400 Invalid request

`too_many_rows`

A bulk endpoint received more rows than its per-call cap.

type invalid_request_error status 400

What happened

`/contacts/batch` and audience attach are capped at 1,000 per call. CSV imports are uncapped (use `contact_imports`).

Chunk the input into sub-batches of ≤1,000, or switch to the async CSV import for very large data.