Clicking a subagent entry during warm-up opens an empty "new agent" tab

Support Bug Reports
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1

Where does the bug appear (feature/product)?

Cursor IDE

Describe the Bug

When the parent agent spawns a subagent (via the Task tool), a clickable entry appears in the chat (e.g., “Explore codebase structure”). During the brief initialization/“warming up” phase before the subagent starts executing, clicking that entry opens a blank “new agent” tab that has no content and doesn’t connect to the actual subagent session.

If you wait until the subagent indicates it has started (spinner changes, status updates), clicking the same entry correctly opens the real subagent window showing its live progress.

The empty tab persists and doesn’t resolve on its own — it remains a dead-end.

Steps to Reproduce

  1. Start a conversation in Agent mode
  2. Give the agent a task that triggers subagent delegation (e.g., a complex exploration or multi-step task)
  3. As soon as the subagent entry appears in the parent chat (during the “warming up” / initialization phase, before it shows active progress), click on it
  4. An empty “new agent” tab opens with no content
  5. Wait for the subagent to fully start, then click the entry again — this time it correctly opens the real subagent window

Expected Behavior

  • Open the real subagent tab (which populates once initialization completes), or
  • Be non-clickable / show a “loading” state until the subagent is ready

Actual Behavior:
A dead-end empty “new agent” tab opens that never connects to the subagent session.

Operating System

MacOS

Version Information

Version: 3.2.21 (Universal)
VSCode Version: 1.105.1
Commit: 806df57ed3b6f1ee0175140d38039a38574ec720
Date: 2026-05-03T01:46:14.413Z
Layout: editor
Build Type: Stable
Release Track: Default
Electron: 39.8.1
Chromium: 142.0.7444.265
Node.js: 22.22.1
V8: 14.2.231.22-electron.0
OS: Darwin arm64 25.4.0

Does this stop you from using Cursor

No - Cursor works, but with this issue

7

This is a known bug. Our team is actively working on a fix. Clicking the subagent card during the brief warm-up phase opens a dead-end tab because the subagent session hasn’t finished initializing yet.

For now, waiting a moment before clicking (as you discovered) is the reliable workaround. The card works correctly once the subagent shows active progress.

A related issue (subagent tabs stuck on “Loading Chat” even after initialization) is being tracked in this thread — your report covers the specific warm-up timing case.