[Resolved: agent API misuse] In-app Browser tab lifecycle after a turn

Resolution

After inspecting the bundled Browser documentation for the affected release, this report does not establish a Codex product defect.

The documented lifecycle is:

• Agent-created tabs are temporary by default.
• tab.markDeliverable() is required for a user-facing page that should remain open after the turn.
• tab.markHandoff() is only for work that should continue in a later agent turn.
• Marks are turn-scoped and must be applied again if the tab is controlled in a later turn.

The reproduction used markHandoff() where markDeliverable() was required, and later controlled the tab again without re-marking it. The disappearing tab was therefore caused by incorrect agent API usage.

I am closing this issue to avoid leaving a misleading bug report. No private URLs, tokens, project contents, or logs were shared.