Cursor does not adhere to the System Prompt unless specifically told to do so.
Windsurf will always read and adhere to the system prompt and it will show as proof within the chat that it has adhered to the prompt. Cursor will ignore the prompt.
For example the system prompt can simply state. “You must follow S.O.L.I.D principles when developing and do not under any circumstance edit the .csproj file”.
Cursor won’t even apply nor acknowledge the rules in any of its chat sessions. It will still create methods that are not single responsibility nor will it say that it followed the prompt when it gives its summary.
In Windsurf you can use the same system prompt and it will adhere to it and also it will acknowledge that it has obeyed it. Also in windsurf you can instruct to it that it has permission to edit the .csproj file and Windsurf will STILL never edit the file. It will tell you that it has specific instructions not to edit it and will not edit it.
In cursor, it will edit the file to its hearts content with no remorse which is unacceptable behavior.
This is on the latest(literally all versions) of cursor.