Cursor Composer/Agent not working on macOS ARM64 - spawn Unknown system error -86 / No first token received

[rupashri (Rupashri Jagadisha)]

Where does the bug appear (feature/product)?

Cursor IDE

Describe the Bug

Machine: Apple Silicon / ARM64 Mac
Cursor Composer/Agent is not working.
The Agent keeps timing out and does not return any response.
Main symptoms:
[composer] No first token received within 2s
[composer] No first token received within 4s
[composer] No first token received within 6s
[composer] No first token received within 8s
[composer] No first token received within 10s
[composer] No first token received within 12s
[composer] No first token received within 14s

Console errors:
[anysphere.cursor-retrieval] spawn Unknown system error -86
[anysphere.cursor-agent-exec] spawn Unknown system error -86
[vscode.git] spawn Unknown system error -86

Additional errors observed:
→ command ‘cursor.action.startTrackingRequest’ not found.
→ agent_exec] [watchdog, LocalReadExecutor]
permissionsService.shouldBlockRead still not completed after 3000ms

Full sample stack trace:

Error: spawn Unknown system error -86
at ChildProcess.spawn (node:internal/child_process:441:11)
at Object.spawn (node:child_process:810:9)
at Object.x [as spawn] (file:///Applications/Cursor.app/Contents/Resources/app/out/vs/workbench/api/node/extensionHostProcess.js:676:1600)
at r (/Applications/Cursor.app/Contents/Resources/app/extensions/cursor-retrieval/dist/main.js:2:2474707)
at /Applications/Cursor.app/Contents/Resources/app/extensions/cursor-retrieval/dist/main.js:2:2474982

Steps to Reproduce

Install Cursor on macOS Apple Silicon / ARM64.
Open any workspace/project.
Open Composer/Agent.
Ask a simple prompt, for example: ‘hi’

Composer stays stuck and keeps logging:
No first token received
Open Developer Tools Console.
Observe repeated errors:

anysphere.cursor-retrieval] spawn Unknown system error -86
[anysphere.cursor-agent-exec] spawn Unknown system error -86
[vscode.git] spawn Unknown system error -86

Expected Behavior

Cursor Composer/Agent should start normally and return a response.
Cursor internal components such as:

anysphere.cursor-retrieval
anysphere.cursor-agent-exec
vscode.git
should not fail with: spawn Unknown system error -86

Screenshots / Screen Recordings

Operating System

MacOS

Version Information

macOS
Darwin arm64 25.5.0
Apple Silicon

Cursor Version Information
Version: 3.10.20 (Universal)
VS Code Extension API: 1.125.0
Commit: 23b9fb205fe595ea2be29da7214e19762d037fc0
Date: 2026-07-07T07:03:33.071Z (2 days ago)
Layout: IDE
Build Type: Stable
Release Track: Default
Electron: 40.10.3
Chromium: 144.0.7559.236
Node.js: 24.15.0
V8: 14.4.258.32-electron.0
xterm.js: 6.1.0-beta.256
OS: Darwin arm64 25.5.0

For AI issues: which model did you use?

i tried all models, nothing is working

Does this stop you from using Cursor

Yes - Cursor is unusable

[Colin]

Hey there!

@rupashri

Version: 3.10.20 (Universal)

Could you try downloading the arm64 build from Cursor · Download instead of the Universal build?

Typically, Unknown system error -86 means that a program is running on the wrong architecture. I’m able to run the Universal build on my Apple Silicon Mac just fine, but this is a good place to start!

[rupashri (Rupashri Jagadisha)]

Update

After clean reinstall and cache cleanup, the issue is still reproducible.

Current version: Cursor 3.10.20
Environment:

Apple Silicon Mac
Darwin arm64 25.5.0

Main repeated failures

[vscode.git] spawn Unknown system error -86
[anysphere.cursor-retrieval] spawn Unknown system error -86
[anysphere.cursor-agent-exec] spawn Unknown system error -86

Composer symptoms
composer] No first token received within 32s

Additional errors
Running Cursor Helper Plugin directly fails:
Command:
/Applications/Cursor.app/Contents/Frameworks/Cursor\ Helper\ \(Plugin\).app/Contents/MacOS/Cursor\ Helper\ \(Plugin\) --version

Output:
(node:6228) [DEP0040] DeprecationWarning: The `punycode` module is deprecated.
FATAL: Unable to find helper app
mach_vm_read invalid address (1)

additionally
ConnectError: [canceled] http/2 stream closed with error code CANCEL (0x8)

Verification performed
Cursor binary: arm64
Cursor Helper (Plugin): arm64
Git works from Cursor terminal
Issue reproduces on hotspot and corporate network
Firewall disable by IT did not help

In my case I consistently see:
[anysphere.cursor-retrieval] spawn Unknown system error -86
[anysphere.cursor-agent-exec] spawn Unknown system error -86
[vscode.git] spawn Unknown system error -86
Composer never receives a first token and eventually times out.

Question: Is this a known issue with Cursor 3.10.x on macOS Apple Silicon, and is there a recommended ARM64 version/workaround to test?

[Colin]

Hey @rupashri

Could you try the workaround steps here?

Cursor 3.7.27 Agent Broken on macOS 27 Beta (Darwin 27) cursor-retrieval spawn failed: Unknown system error -86

yeap, Try these steps in order: Install Rosetta 2 (most common fix): Open Terminal and run: softwareupdate --install-rosetta Then restart Cursor. Remove quarantine attributes: Fully quit Cursor and run: xattr -cr /Applications/Cursor.app Then relaunch. Disable Instant Grep indexing: Cursor Settings > Indexing & Docs > turn off “Index Repositories for Instant Grep (BETA)”, then restart Cursor. The -86 errors often originate from the retrieval extension this feature uses, which mat…

I do think we might have a bug on our hands, would like to have a second confirmation that this fixes the issue!

[rupashri (Rupashri Jagadisha)]

Hi Colin,

Good news — it’s working now!

I updated to:

Version: 3.11.19
Commit: bf249e6efb5b097f23d7e21d7283429f0760b740
OS: Darwin arm64 25.5.0

Composer/Agent is now responding normally.

I also went through the troubleshooting steps you suggested, including:

• Installing Rosetta (where applicable)

• Removing quarantine attributes:
  xattr -cr /Applications/Cursor.app
  Testing different network configurations

The issue appears to be resolved on 3.11.19.

Thanks for your help and for looking into this. I appreciate it!

Regards, Rupashri