So I open my agent thread on cursor.com and Im met with this
The console errors are the following
POSThttps://cursor.com/api/dashboard/get-team-commands[HTTP/2 401 161ms]
Error: cannot encode field aiserver.v1.ConversationMessage.ToolResult.result to JSON: E(…).toJson is not a function
How do I fix this? I really need access to this thread now!
Hi!
This is a known issue we’re tracking. There’s an active thread with reports and updates here: “Cursor background agents completely unusable.”
The console serialization error you’re seeing (ToolResult.result … toJson is not a function) matches the same bug others are hitting across different models and browsers, and it can block the entire Agents page (not just one run).
A couple of things that sometimes help temporarily:
Hard refresh (Cmd+Shift+R) and reopen from the main list at cursor.com/agents
On macOS, try Safari (it behaves differently for some users)
No guaranteed workaround yet, but the eng team is on it.
If you need the output right now, it’s worth checking whether the agent pushed commits to your branch, in some cases the work is there even when the web thread won’t load.
Best,
Mohit
It started working randomly yesterday
