Agent stream bug

[Anmol_Agrawal]

Where does the bug appear (feature/product)?

Cursor IDE

Describe the Bug

The agent stream failed to start. Please reload the window to continue.

Steps to Reproduce

As soon i type in chat. i got this error

Screenshots / Screen Recordings

Request ID: 69b2e302-695d-4747-a344-d311787ca59d
{“error”:“ERROR_EXTENSION_HOST_TIMEOUT”,“details”:{“title”:“Agent Stream Start Failed”,“detail”:“The agent stream failed to start. Please reload the window to continue.”,“isRetryable”:false,“shouldShowImmediateError”:true,“additionalInfo”:{},“buttons”:[{“label”:“Reload Window”,“reloadWindow”:{}}],“planChoices”:[]}}
Agent Stream Start Failed [deadline_exceeded]
ConnectError: [deadline_exceeded] Agent Stream Start Failed
at vscode-file://vscode-app/Applications/Cursor.app/Contents/Resources/app/out/vs/workbench/workbench.desktop.main.js:11441:39887

Operating System

MacOS

Version Information

Version: 2.4.31 (Universal)
VSCode Version: 1.105.1
Commit: 3578107fdf149b00059ddad37048220e41681000
Date: 2026-02-08T07:42:24.999Z
Build Type: Stable
Release Track: Default
Electron: 39.2.7
Chromium: 142.0.7444.235
Node.js: 22.21.1
V8: 14.2.231.21-electron.0
OS: Darwin arm64 24.6.0

Does this stop you from using Cursor

yes

[deanrie]

Hey, thanks for the report. This is a known issue. The extension host can hang while initializing the agent, which leads to ERROR_EXTENSION_HOST_TIMEOUT / deadline_exceeded. A few things you can try:

1. Disable MCP servers (if you have any): Cursor Settings > Tools & MCP, disable everything and restart Cursor.

2. Clear the global state database:

   • Fully quit Cursor
   • Delete or rename: ~/Library/Application Support/Cursor/User/globalStorage/state.vscdb
   • Restart Cursor (you’ll need to sign in again)

3. Start without extensions:

   cursor --disable-extensions
   

   If that works, re-enable extensions one by one to find the one causing the issue.

4. If nothing helps, try downgrading to an earlier version: Cursor · Download

Related threads with more context:

• Agent-execution-time-out
• After last update, stuck at “Waiting for extension host”

The team is aware and is tracking this. Let me know what worked for you.

[aeyarr]

I tried all the options.

1. Disabled all MCP servers and extensions - no dice
2. Deleted the vscdb file and restarted, ended up losing all models that existed and was unable to add new ones, none found. Had to restore the old version of the vscdb file
3. Downgraded to older version - no change