Where does the bug appear (feature/product)? Cursor IDE Describe the Bug Environment: OS: Linux 6.6.87.2-microsoft-standard-WSL2 (WSL2) Shell: zsh Mode: Ask mode (read-only) Issue: Agent tool calls intermittently fail with backend errors. Two distinct error messages observed: Read / Glob / Gr…

I haven’t been able to work for the past 2 hours… Am I the only one ?

The model just told me : Current status (just tested all three): Tool Status Read :white_check_mark: Working Shell :cross_mark: Command failed to spawn: Execution backend unavailable Glob :cross_mark: Execution backend unavailable So it’s back to the partial-outage state: file reads…

I have been trying to debug for 2 hours : Symptom: Agent tool calls fail persistently: Shell → Command failed to spawn: Execution backend unavailable Glob/search → Execution backend unavailable File writes (edits) → same error, with Do not retry — execution environment is down Read of workspace f…

Hi @Clem_B Thanks for the forum post and I apologize for the instability you are facing. This is a known class of issue regarding Windows + WSL2. the agent’s tools (Read, Grep, Glob, Shell) all run through the WSL2 extension host, so when that host crashes or briefly stops responding, they all repor…

Thanks @kevinn , really appreciate the quick response. I’ve now worked through your whole list and unfortunately it still isn’t recovering, so I think this might be more than the usual flicker. What I’ve done from your steps: I fully quit and reopened Cursor (not just a reload) confirmed I’m on …

I’m still debugging for each test below, I open the workspace/folder fresh and ask a new chat to run echo ok — that’s my pass/fail check for whether the execution backend is working. :red_circle: Opened with extensions disabled (cursor --disable-extensions) → still fails (rules out extensions, in…

More findings since my last post :green_circle: The biggest one: I copied the whole project to a different path and opened that. The copy works flawlessly — the agent runs echo ok, edits files, everything. The original path keeps failing. Identical content; the only difference is the workspace path…

I manage to unblock myself by just moving Cursor\User\globalStorage\state.vscdb and reopening my project. I think something was corrupted in there (not sure why) but I definitely lots a lot of personal info there… Was there any other way to fix my issue without doing something so extreme ?

I am experiencing the same issue. I was using Cursor for SDD when the error ‘Command failed to spawn: Execution backend unavailable’ appeared. Now I am completely blocked, and restarting the entire system didn’t fix it. Similar to the comment above, I am also running WSL2.

This has been happening intermittently since mid-June. I would sometimes be able to resolve it by restarting WSL, or my entire PC. With the latest update, Cursor is now completely bricked in this setup. Nothing I do fixes it (Grok and Cursor auto would suggest removing some folders, caches, etc.).…

Intermittent "Execution backend unavailable" errors blocking all tool use

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thibauld (Thibauld Favre) July 1, 2026, 10:49pm 20

Fwiw, I just posted a full report made by a working cursor-agent asked to troubleshoot his big brother’s state: Execution backend unavailable - #95 by thibauld

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Intermittent "Execution backend unavailable" errors blocking all tool use

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