Can't send any message to the agent

[h0nyik]

Where does the bug appear (feature/product)?

Cursor IDE

Describe the Bug

I am having trouble sending instructions to the agent. It always works fine for a while after starting Cursor. However, after a while, out of nowhere, I suddenly cannot send any messages. I have tried various available models, I have even tried changing from agent to ask, but nothing helps. I always have to restart the entire application or create a completely new chat. This greatly disrupts my workflow and is annoying. Does anyone have a solution, please?

Here is video of that problem: https://roztisk.s-ul.eu/Pl5b5i5J

Steps to Reproduce

I don’t know, it happens out of nowhere

Expected Behavior

sending messages smoothly

Screenshots / Screen Recordings

Operating System

Windows 10/11

Current Cursor Version (Menu → About Cursor → Copy)

Version: 1.5.9 (user setup)
VSCode Version: 1.99.3
Commit: de327274300c6f38ec9f4240d11e82c3b0660b20
Date: 2025-08-30T21:02:27.236Z
Electron: 34.5.8
Chromium: 132.0.6834.210
Node.js: 20.19.1
V8: 13.2.152.41-electron.0
OS: Windows_NT x64 10.0.26100

Does this stop you from using Cursor

Sometimes - I can sometimes use Cursor

[deanrie]

Hey, thanks for the report. You might have a large file open in a tab, and even if it’s not in context, the chat can see it and this might cause an error. Try closing all open file tabs, creating a new chat, and trying again. Let me know if this helps.

[gallo2000sv (Enrique)]

Same issue. No open files, opened a new conversation, 2 minutes after same problem again. Exactly the same, Happened yesterday and rebooted cursor, updated cursor, rebooted windows, rebooted my Ubuntu server. Same behaviour.
No error message, nothing. Just stopped working.

[h0nyik]

Yes, there really isn’t much to prevent this but. It happens to me sporadically ± regardless of what I’m working with at the moment. I’ve also tried all of the above, but still the error happens all the time.