DevContainers still broken (by Cursor, for no reason?)

Where does the bug appear (feature/product)?

Cursor IDE

Describe the Bug

DevContainers worked 100% for 2024 and almost all of 2025.

Then AnySphere published a custom, buggy, badly written ‘alternative’ extension and tricked people into installing it. It’s like DevCotnainers, but … broken in multiple ways.

The original devcotnainers is now missing from the cursor marketplace.

As per this thread: Devcontainers extension broken, can't create a dev container - Cursor’s custom DevContainers still broken at a basic level: you literally cannot create a DevContainer.

What’s the workaround? We can’t “use the agent” since the cursor agent CREATES THE WRONG CONTAINER half the time (it guesses, and makes stupid guesses, wasting huge amounts of time … when the IDE itself already has the feature built-in and working 100% reliably).

Steps to Reproduce

Use cursor. Attempt “open folder in devcontainer”. Microsoft’s own official definition of this feature is that it MUST create a devcontainer automtically - Cursor’s custom implemenation fails to uphold the contrtact.

Expected Behavior

Work exactly as it did for the last 2 years.

Operating System

Windows 10/11

Current Cursor Version (Menu → About Cursor → Copy)

Version: 2.2.20 (user setup)
VSCode Version: 1.105.1
Commit: b3573281c4775bfc6bba466bf6563d3d498d1070
Date: 2025-12-12T06:29:26.017Z
Electron: 37.7.0
Chromium: 138.0.7204.251
Node.js: 22.20.0
V8: 13.8.258.32-electron.0
OS: Windows_NT x64 10.0.19045

Does this stop you from using Cursor

Yes - Cursor is unusable

… and as far as I can tell: Cursor’s custom implementation of devcontainers is currently (december 2025) incompatible with the devcontainer spec / microsoft’s reference implementation. Analysis of the logs suggest Cursor tries to init a diffrent docker container than MS / Vscode would, and that Cursor requires a custom devcontainer.json - suggesting its even more important that cursor reinstates the working ‘autogenerate the devctonainer file’ that previously worked for 2 years.

The previous response ‘let the agent do it’ is insulting and stupid: the agent will not run while these errors are in progress.

Hey, thanks for the report. I understand the frustration - this is indeed a serious issue.

Similar reports: Devcontainers extension broken, can't create a dev container

Unfortunately, this is a known limitation of the Anysphere DevContainers extension - it doesn’t provide a wizard to select prebuilt templates like the original Microsoft extension does.

For now, the only options are:

  • Manually create the .devcontainer/devcontainer.json with the needed configuration
  • Or temporarily use VS Code with the Microsoft extension for setup, then switch back to Cursor

I’ll pass on to the team that this is critical for many users’ workflow - auto-generation of devcontainer.json needs to come back.

This is something we’re looking at adding.

Re: using the agent to set up the dev container: does this work if you open Cursor outside of the devcontainer (i.e. open the folder locally?). The agent should be able to work on the devcontainer files in that environment.

This topic was automatically closed 22 days after the last reply. New replies are no longer allowed.