Poll a long-running task created by this server. Repeat until status is "completed" or "failed".

Deliver input that a paused task (status input_required) asked for.

Cooperatively cancel a running task. The task stops at its next checkpoint.

Simulates a slow job (~2s per section). Demonstrates background execution, progress polling, restart-safe state, and cooperative cancellation.

Open a chunked upload or download session. Upload: send chunks with file_transfer_write starting at offset 0, then file_transfer_commit. Download: fetch chunks with file_transfer_read until eof. Sessions survive server restarts — resume at the reported nextOffset.

Append a base64 chunk at the session's expected offset. A wrong offset returns a repairable error with the correct cursor instead of failing the transfer.

Fetch a byte range as base64. Repeat with nextOffset until eof; the final response carries the whole-file sha256.

Verify size and sha256 (when declared), then move the staged file to its destination.

Report direction, status, bytes received so far, and destination — useful after a restart.