Write events from any program into the work graph log [write]

Appends up to 500 events in the same envelope GET /events returns, from an agent running elsewhere, a script or your own app. Each event's idempotency_key is unique per log: pushing it again answers status duplicate with the existing id and writes nothing. log person (default) is your private log; workspace is your workspace's shared log. task_id or session_id must be one you can open. bodies are kept whole, whatever their size: text or base64 inline, or file_id of a file uploaded first through POST /files/uploads for large ones; credentials in text bodies are masked before storage. source.system names your program; the platform's own systems are refused (400 reserved_source). The whole batch is checked before anything is written.