Hey, thanks for the report. There’s one important thing that’ll save you a lot of time. These three things aren’t configured via the agent. They come from language extensions and formatters, not some checkbox in settings. So when the agent edits settings.json, it’s more likely to break your config than fix it.
How to set it up manually in a reliable way:
Error underlines plus Go to Definition F12
This is handled by the language server from the extension for your language. Install the right extension:
Python → Python plus Pylance
C/C++ → C/C++
JS/TS → already built in
Go, Rust, etc. → the official language extension
After you install it, squiggles and F12 should work automatically.
Format on Save
Turn on editor.formatOnSave: true in settings and set a formatter via editor.defaultFormatter, for example Prettier for JS/TS, or clang-format or Black for your stack. Brace alignment { } is controlled by the formatter’s rules.
Tell me what language or stack you’re using and where you’re trying to set this up, the normal editor or the Agents Window, and I’ll share the exact extension names and a settings snippet for your case.
And for the future, it’s better to install these manually from the Extensions panel instead of asking the agent to edit settings, so nothing gets overwritten.
Hey! Thanks for getting back to me!
I’m using Windows 10 and I write code in MQL5. I’ve tried configuring it both manually and using the Agent. These are the extensions that the Cursor Agent installed in Cursor.
There are some settings that I cannot configure manually because they are not available in the UI, such as “Render Validation Decorations.”
I’m sharing this feedback because I believe Cursor needs to improve the experience so that users can easily and quickly configure these basic settings for any programming language. Cursor Agent is supposed to be a coding agent, not just a code editor.
Thanks for breaking down the details, it’s clearer now. I can see the installed extensions in the screenshot, including MQL Tools L I V. That’s the key point. MQL5 is a niche language, and there’s no built-in language server for it in Cursor or VS Code, so these features don’t work like they do in popular stacks like Python or JS.
Let’s go through it for MQL5:
Error underlines
In MQL, these don’t come from real-time analysis. They come from syntax check or compilation via MetaEditor, which MQL Tools runs. To make this work, you need to set the path to MetaEditor. The most reliable way is not to set it manually, but to run this command: Ctrl+Shift+P then MQL: Create configuration. It will generate the needed settings. If you do edit settings.json by hand, the exact key name for MQL5 is mql_tools.Metaeditor.Metaeditor5Dir and mql_tools.Metaeditor.Metaeditor4Dir for MQL4. Set it to the folder path that contains metaeditor64.exe. After that, syntax check should start highlighting errors.
Render Validation Decorations
This option isn’t in the UI, but you can add it manually in settings.json:
"editor.renderValidationDecorations": "on"
Values are on or off or editor. Open settings.json via Ctrl+Shift+P then Preferences: Open User Settings (JSON).
Go to Definition F12
MQL Tools gives autocomplete and MQL help, but full go-to-definition for MQL is only partly supported. That’s a limit of the language extension, not Cursor.
Format on Save with aligned { }
Honestly, there isn’t a stable MQL5 formatter in the ecosystem that can align braces the way you want. You can enable editor.formatOnSave: true, but without a formatter that understands MQL, it won’t align braces.
One important tip. It’s better to set these things manually via Extensions and settings.json or via MQL: Create configuration, rather than asking an agent to edit your config. It’ll likely overwrite existing settings, like you noticed.
About the feedback, I agree setting up the environment for a language should be simpler. I passed it to the team as a request. If you share your current settings.json, I can help you put together a working setup for MQL5.
Previously, when I was using VS Code, I configured everything manually, and VS Code worked very well with these basic configuration requirements.
I think you may have misunderstood a little when you said, “Honestly, there isn’t a stable MQL5 formatter in the ecosystem that can align braces the way you want.” I use multiple computers, and VS Code is installed on all of them. I have been using it reliably for years.
Now, I’m using Cursor Agent Pro because I want an AI agent to assist me with coding, not simply a code-writing environment. I wanted to test Cursor Agent’s ability to handle a very basic request that is common for users, especially beginners who are just getting started with a code editor. That is why I asked the Agent to handle this configuration.
I have also been very patient and have spent the past three days working with the Agent just to configure these basic settings. My purpose was to experience the Agent’s capabilities and its way of working, because I’m looking for an AI coding companion that I can work with over the long term, not just temporarily.
“Master the basics and small things before taking on bigger things!”
My posts are intended to share my genuine experience as a real user, but always in good faith and with the intention of providing constructive feedback. I hope this can help improve the Agent. If the Agent can improve on basic, small tasks first, that will build trust and make it easier for users to rely on it for more complex tasks.
The Agent and I have now completed all of the configuration requirements.
Although it took far too much time, I still have a positive overall impression of the Agent!
