Generated files disappear

It works while you are testing, and the files are gone later - with no error anywhere to explain it.

The cause is nearly always that output stayed in a sandbox instead of being published as an artifact. A sandbox is temporary execution space. It is not durable storage, and it is not something a user can reliably reach.

The fix is on both sides:

• The agent should publish results as artifacts using its file or blob tools.
• Its instructions should never tell a user to fetch a file from a workspace path.

Artifacts carry retention and provenance independent of any workspace.

Next

• Return artifacts - the durable handoff.
• Work with files - attachments, artifacts, and the sandbox boundary.
• Configure file storage - local versus S3-compatible backends.