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Cursor No Resource Accessor Found for Composer

When Cursor logs No resource accessor found for composer, open a real project folder, repair an empty code-workspace file, and start a new chat.

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Last checked
Sep 11, 2026
Applies to
Windows, Mac, Desktop
Fix status
Community Confirmed
Fastest useful check

Quick answer

Match No resource accessor found for composer followed by a UUID in Cursor's error details or logs. If Explorer says NO FOLDER OPENED, choose File → Open Folder and open a real project, then start a new chat. If you opened a .code-workspace file, make sure its folders array is not empty, save it, and reload the window. If the old composer remains stuck, open a new window, reopen the project, and move needed context into a new chat. Do not start with HTTP/1.1, MCP disable, certificate changes, or reinstalling: this fingerprint is a local workspace-to-composer binding failure before the request reaches the network.

On this page

What we're seeing

  • The phrase lock is No resource accessor found for composer, usually followed by a composer UUID.
  • Cursor may surface the same local failure as Connection failed. Please try again, or contact support if the issue persists, or as An unexpected error occurred. The internal composer sentence distinguishes it from network twins.
  • Independent June–July 2026 first-hand Cursor forum reports quote the exact composer sentence with NO FOLDER OPENED or an empty folders array in a .code-workspace file.
  • Opening a real project folder, repairing the workspace folder entry, and starting a new chat restored Agent or Chat in those reports.
  • Green Network Diagnostics and a pre-send failure support the workspace/composer branch, not HTTP, MCP, or TLS troubleshooting.

Start here

Try these first

Fix 1

Confirm No resource accessor found for composer

Community Confirmed

The visible toast can imitate a network error. Require the internal composer sentence before using workspace leftovers.

  1. Open the error details, Developer Tools console, or Cursor logs for the failed chat.
  2. Confirm the text says No resource accessor found for composer followed by a UUID.
  3. Check Explorer for NO FOLDER OPENED and note whether the window came from a .code-workspace file.
  4. If that internal sentence is absent and Network Diagnostics fails, stop here and use the separate Connection failed guide.

Applies to Windows, Mac, Desktop

Fix 2

Open a real project folder

Community Confirmed

A June 2026 first-hand report with the exact composer sentence cleared as soon as Cursor had a real folder to bind to the chat. Cursor staff described it as a client-side bug, not a network failure.

  1. If Explorer shows NO FOLDER OPENED, choose File → Open Folder.
  2. Select the real project folder you want Cursor to use.
  3. Wait for the folder to finish opening, then start a new chat and retry the request.

Applies to Windows, Mac, Desktop

Fix 3

Repair an empty .code-workspace file

Community Confirmed

First-hand reports after an update show the composer losing its resource when a .code-workspace file contains an empty folders array. Adding the project path restores the binding.

  1. Open the .code-workspace file used by the affected window.
  2. If it contains an empty folders array, add a real project entry such as a path set to the current folder instead of leaving the array empty.
  3. Save the workspace file, then run Developer: Reload Window.
  4. Start a new chat after the project appears in Explorer.

Applies to Windows, Mac, Desktop

Fix 4

Open a new window and start a new chat

Community Confirmed

An old composer UUID can stay detached after the workspace is repaired. July 2026 first-hand reports recovered in a new window with a new chat.

  1. Choose File → New Window.
  2. Use File → Open Folder to open the affected project.
  3. Start a new chat instead of retrying the dead composer repeatedly.
  4. Copy only the context you still need from the old chat into the new one.

Applies to Windows, Mac, Desktop

Fix 5

Rule out the network twins

Community Confirmed

HTTP/1.1, MCP disable, and System Certificates V2 belong to separate Cursor fingerprints. They are not first moves when the logs name a missing composer resource.

  1. Run Network Diagnostics only to confirm the checks are green.
  2. Do not switch to HTTP/1.1 merely because the visible toast says Connection failed.
  3. Do not disable MCP or change certificates unless the exact screen changes to one of those separate fingerprints.

Applies to Windows, Mac, Desktop

Device notes

Windows
File → Open Folder and .code-workspace repair apply on Windows. The exact internal composer sentence matters more than the generic toast.
Mac
Use the same folder and workspace repair path on macOS. Start a new chat after reopening the project.
Desktop
This failure occurs before the request reaches Cursor's network path. A real folder and fresh composer are the primary leftovers.

Official information

Checked on 11 September 2026, Cursor staff replies in forum threads quoting No resource accessor found for composer describe a known client-side workspace/composer binding failure that occurs before a network request. First-hand reports confirm opening a folder, repairing an empty .code-workspace folders array, and starting a new chat as try-today leftovers. Cursor does not publish a separate Help Center article for this exact internal sentence.

Sources

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