Cheetah model rapid tool calls cause listener leak crashes (code: 5) on macOS

Bug Reports
1

Where does the bug appear (feature/product)?

Cursor IDE

Describe the Bug

Bug Report: Cheetah Model Rapid Tool Calls Cause Listener Leak Crashes

Environment

  • OS: macOS darwin 24.6.0
  • Cursor Version: 1.7.54 (stable)
  • Model: Cheetah
  • MCP Servers: GitHub, CircleCI, Playwright, Linear

Symptoms

Cursor crashes with CodeWindow: renderer process gone (reason: crashed, code: 5) after rapid AI tool calls in a single chat window.

Root Cause

Listener leak in chat-specific renderer windows:

  • MCP tools create event listeners for each tool call
  • Listeners are not cleaned up between rapid executions
  • Accumulation (175-263 listeners) overwhelms renderer
  • Chat-scoped issue (window2 affected, window1 clean)

Steps to Reproduce

Context: User wanted PR information across multiple repos (Bumblebee, Transwarp) including:

Open PRs
Merged PRs from past week
Across ALL repos they’ve touched
With collaborators, status, etc.
Reproduction Steps
What Happened
User asked: “Get PRs from all repos I’ve touched in past week”
AI (Cheetah model) responded with rapid-fire tool calls to:
Query GitHub for PRs across multiple repos
Search through repo structure
Read PR details, reviewers, status
Format results
Executed: 100+ tool calls including:
GitHub API calls (mcp_github_search_pull_requests)
Repository searches
PR detail fetches
Multiple simultaneous operations
Result: Listener leak detected after ~80-100 calls, renderer crashed

Expected Behavior

properly call tools without overloading cursor and crashing - it appears cheetah is too fast

Operating System

MacOS

Current Cursor Version (Menu → About Cursor → Copy)

Environment

  • OS: macOS darwin 24.6.0
  • Cursor Version: 1.7.54 (stable)
  • Model: Cheetah
  • MCP Servers: GitHub, CircleCI, Playwright, Linear

For AI issues: which model did you use?

cheetah

Does this stop you from using Cursor

Sometimes - I can sometimes use Cursor

2

Hey, thanks for the report. This matches our ongoing investigation into renderer crashes (code: 5) during MCP operations.

While we investigate, please try:

  • Launching with cursor --disable-gpu
  • Temporarily disabling some MCP servers to see if a specific one triggers it (especially GitHub, Atlassian)
  • Checking whether this reproduces in other projects with the same MCP setup

The pattern you described (Cheetah making 100+ rapid tool calls), together with the listener leak finding, will help the team fix this. Thanks for the thorough investigation.

3

Hey Dean, thanks for the quick reply!

I’m curious if the leak might be due to the mcp provider? Or does Cursor manage the listeners itself?

Also I only had the four MCP above mentioned (no Atlassian)

Checking whether this reproduces in other projects with the same MCP setup - I think it does but I’ll check.

1 Like
4

Hardware: MacBook Pro with Apple M4 Max chip, 36 GB RAM
OS: macOS 15.6 (Build 24G84)

Also thought I’d list my hardware - given… I don’t think its a hardware issue on my end

1 Like
5

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