Gumpbox 1.12.4: Agent File Transfers, Fixed

Gumpbox 1.12.4 fixes a crash in the agent file-transfer flow: on 1.12.3, the moment an AI agent requested an upload or download through the Global MCP server, the app could quit outright — before the approval dialog ever appeared. The transfer was never approved or denied, because the thing you approve with was gone. This post covers what broke, what 1.12.4 changes, and how the approval flow behaves now.

What happened

File transfers requested by an agent are user-mediated by design: every upload and download pauses for a confirmation sheet showing what will move, where, and on whose behalf. In 1.12.3, preparing that sheet crashed the app itself. Any file_transfer.upload or file_transfer.download request — a 79-byte text file or a 12 MB tarball, size made no difference — quit Gumpbox instantly with a memory-ownership fault, 3 out of 3 times, before the dialog could render.

The trigger was a database fetch that resolved which server the transfer targets. It ran on a background database context that wasn't bound to the store's execution queue, and reading the server's credential relationship tripped a fatal consistency check. A crash like that can't be caught from inside the app — the only fix is to do the work on the right context, which is what 1.12.4 does.

What's fixed

• The approval sheet appears, every time. Agent-requested uploads and downloads now open the confirmation dialog reliably, so you always get the final say. Approve and the transfer runs; deny and the agent receives a clean user-cancelled result — the app stays up either way.
• The sheet shows the target server. The approval now consistently displays the server's name and host badge in the session details, so you can see at a glance which machine a file is headed to.
• The same path is hardened for browser agents. The identical off-main fetch pattern sat underneath the browser-use authorization gate too; 1.12.4 fixes it there as well, before it could ever bite.

We verified the flow end to end: request a Trusted session, upload a file to a remote server, download it back, and diff the contents — byte-identical, with the app alive through every step, approvals included.

Availability

Gumpbox 1.12.4 is available for Mac as a direct download today. The fix applies to every tier.

Download Gumpbox on the App Store