Say Goodbye to Free Trial Limits: Reset Your Cursor AI Machine ID with This Python Script

I. The Spark: When AI Hits the Paywall

Cursor’s AI features are a game-changer, supercharging development on top of the familiar VS Code base. That intelligent code completion, the quick refactoring, the chat-based assistance – it feels like magic... until the magic runs out.

For Linux users running the AppImage version, there's a common hurdle: the free trial limit. Hit that quota (currently seems to be 3 accounts) tied to your unique machine ID, and you're suddenly staring at that frustrating message:

You’ve exceeded the number of free trial accounts allowed for machine-id: 12345XXXXX-XXXXXXX…

Suddenly, your options narrow:

1. Jump through hoops setting up your entire dev environment on a new machine and enjoy a few more free trial accounts before having to do it all over again (assuming you even have access to an unlimited number of dev servers).

2. Shell out for a subscription, (around $384/per user/per year at the time of writing).

or watch your powerful AI assistant revert to a standard VS Code experience.

Sound familiar? I hit this wall too. Faced with losing the AI capabilities or paying up, and considering Cursor's relationship with the open-source community, I got curious. How exactly does Cursor's AppImage identify a machine? Could that mechanism be... adjusted? After some digging into the AppImage internals, I found that the answer was yes. The vulnerability involves more than just clearing config files, touching on how the application itself references system identifiers.

The good news? I've automated the entire reset process into a Python script. This post is your deep dive into how that script works, exploiting the way Cursor handles machine IDs to give you a fresh start with a single command, and how you can use it yourself. Let's get started.

II. What is a Machine ID? How Cursor Identifies Your Machine

Software often needs a way to distinguish between different installations or machines. On Linux, a common system-wide unique identifier is found in /etc/machine-id. Applications might read this file directly or use libraries that access it.

Cursor, based on its configuration file (storage.json), appears to use several identifiers:

• telemetry.machineId: Likely a primary identifier for telemetry.

• telemetry.macMachineId: Another ID, potentially mimicking a MAC address format.

• telemetry.devDeviceId: Seems like a standard device identifier (UUID).

• telemetry.sqmId: Another UUID, often related to software quality metrics.

These values are stored in ~/.config/Cursor/User/globalStorage/storage.json. If Cursor also uses the static /etc/machine-id directly within its code, simply changing storage.json might not be enough for a complete identity reset. The script I developed addresses both the stored configuration and how the application determines one of these IDs internally.

III. Under the Hood: How the Script Works

The script tackles the machine ID reset with a two-pronged attack / approach: it generates new IDs and updates the configuration file, and it patches the Cursor application code within the AppImage itself.

Part 1: Refreshing the Configuration (storage.json)

1. Generate New IDs: The script uses Python's uuid module to create fresh, random identifiers:

   • A long random ID for telemetry.machineId (combining two UUIDv4 hex strings).

   • A MAC-like ID for telemetry.macMachineId (using parts of a UUIDv4).

   • Standard UUIDv4s for telemetry.devDeviceId and telemetry.sqmId.

2. Locate & Backup: It finds the storage.json file in the standard Cursor config path. Crucially, it creates a backup (storage.json.bak) before making any changes.

3. Update JSON:

   • It reads the existing JSON data.

   • It updates the values for the four specific keys (telemetry.machineId, telemetry.macMachineId, telemetry.devDeviceId, telemetry.sqmId) with the newly generated IDs.

   • It offers an option to use the external command-line tool jq for this update if it's installed and the user prefers it (as jq can sometimes be more robust for complex JSON manipulation via CLI).

   • If jq isn't used or available, it falls back to Python's built-in json module to write the updated data back to storage.json, ensuring proper formatting.

Part 2: Patching the Application (AppImage Internals)

This is the more invasive, but potentially necessary, step.

1. Extract AppImage: The script runs the Cursor AppImage file with the --appimage-extract argument. This unpacks the entire application into a temporary directory, typically named squashfs-root.

2. Modify JavaScript: It targets specific JavaScript files within the extracted application core, namely:

   • squashfs-root/usr/share/cursor/resources/app/out/main.js

   • squashfs-root/usr/share/cursor/resources/app/out/vs/code/node/cliProcessMain.js (Note: These paths might change in future Cursor versions)

3. Apply Regex Patch: Using Python's re.sub (regular expressions), it searches these files for code patterns that look like string literals containing /etc/machine-id (e.g., ".../etc/machine-id..."). It replaces these occurrences with the literal string "uuidgen".

   • Why? This changes Cursor's behavior. Instead of trying to read the static system ID from /etc/machine-id, the modified code will now execute the uuidgen command whenever it needs that specific ID. uuidgen generates a brand new random UUID each time it's run, effectively decoupling this part of Cursor's identification from the static system ID.

4. Repack AppImage: The script uses the appimagetool utility (it downloads a compatible version using requests if not found at /tmp/appimagetool) to repack the modified squashfs-root directory back into an AppImage. This newly created AppImage overwrites the original one provided by the user.

Behind the Scenes: Helper Functions

The script also includes several helper functions: argparse to handle the --appimage command-line argument; os, pwd, and shutil for file operations (path validation, finding home dir, copying backups, checking for uuidgen/jq); psutil to find and forcefully kill any running Cursor processes before making changes (to prevent conflicts); and time.sleep for brief pauses.

IV. Get Started: Running the Reset Script

Ready to give it a try? Here's how:

Prerequisites: What You'll Need

• A Linux environment.

• Python 3 installed.

• The Python libraries psutil and requests. Install them if needed:

    pip install psutil requests
  

• Your downloaded Cursor AppImage file (e.g., Cursor-0.xx.x.AppImage).

  You can download the official Cursor AppImage here

• The uuidgen command available (usually installed by default on most Linux distributions).

• (Optional) The jq command-line JSON processor if you want to use that update method.

Here is the complete Python script cursor_reset.py):

Step-by-Step Guide

1. Save the Script: Copy the Python script code (you can copy it directly from the gist embed above 👆) and save it to a file, for cursor_reset.py.

2. Close Cursor: Ensure Cursor is completely closed. The script tries to kill processes, but it's best practice to close it manually first.

3. Open Terminal: Launch your terminal.

4. Navigate: Use cd to go to the directory where you saved cursor_reset.py.

5. Run the Command: Execute the script, providing the path to your Cursor AppImage:

    python cursor_reset.py --appimage /path/to/your/Cursor-0.xx.x.AppImage
   

   (Replace /path/to/your/Cursor-0.xx.x.AppImage with the actual path).

6. Follow Prompts: If jq is detected, the script will ask if you want to use it (Y/N).

7. Wait: The script will output its progress (killing processes, extracting, modifying, repacking). Extraction and repacking can take a minute or two.

8. Check Success Message: Look for the "Successfully updated all IDs" message and the list of new IDs printed at the end.

9. Launch Modified AppImage: Run your modified Cursor AppImage file as usual. It should now appear as a fresh installation regarding these specific IDs. Most importantly, you should now be able to create and use new free trial accounts over and over again on the same machine, even after hitting your initial trial account limit.

   Remember to run the Python script to patch your Cursor AppImage anytime you:

   • Exceed your machine's trial account limit

   • Update or download a new Cursor AppImage version.

Quick Notes:

• The script will attempt to kill running Cursor processes. Save your work first!

• It modifies your original AppImage file in place. Consider backing up the original AppImage beforehand if you're cautious.

• A backup of your configuration is created (storage.json.bak) in the same directory as storage.json.

V. Behind the Code: Design Decisions

Why go through the trouble of patching the AppImage?

Why Patch the AppImage Directly?

Simply changing storage.json is not sufficient. This leads me to believe that Cursor's code also directly reads the static /etc/machine-id (or uses a library that does) for identification. The patch intercepts this retrieval within the application code, forcing it to use the dynamic uuidgen command instead, making that part of the identity reset more robust.

Python: The Right Tool for the Job

Python excels at this kind of task: managing files (os, shutil), handling JSON (json), running external processes (subprocess, psutil), making web requests (requests), and text manipulation (re).

Adding Robustness (jq, psutil, requests)

Using psutil provides a reliable way to find and terminate processes. Offering jq gives an alternative, often very robust, method for CLI JSON editing. Downloading appimagetool via requests makes the script more self-contained for users who don't have it installed system-wide.

VI. Read Before Running: Risks and Responsibilities

Before you run this script, please understand:

• Potential Instability: Modifying application internals (the JavaScript files) carries risks. Future Cursor updates might change the code structure, breaking the script or causing the modified AppImage to become unstable or fail to launch. Use at your own risk.

• App Updates: When you download a new Cursor AppImage version, this patch will be gone. You will need to re-run the script on the new AppImage file if you want to apply the changes again.

• Terms of Service: Using scripts like this specifically to circumvent trial limitations or usage restrictions almost certainly violates Cursor's Terms of Service. Be aware of this. This post provides the script for technical exploration and understanding; how you use it is your responsibility.

• Linux AppImage Only: This script is tailored specifically for the Linux AppImage distribution of Cursor. It relies on Linux paths (/etc/machine-id), AppImage structure, and tools (uuidgen, appimagetool). It have not tested it on Windows, macOS, or other installation methods.

• Security Note: The script downloads appimagetool directly from its official GitHub releases page if needed. While this is standard practice for obtaining appimagetool, be aware you are downloading and executing code from the internet.

VII. Wrapping Up

This Python script offers a way to reset various identifiers (machine IDs) used by Cursor Linux AppImage, employing a combination of configuration file updates and direct patching of the application code. It automates a process that would be tedious and error-prone to do manually.

It serves as an interesting proof of concept for a vulnerability I found within Cursor’s Linux AppImages as well as exploiting that vulnerability and effectively modifying application behavior through Python scripting. However, remember the caveats – particularly regarding potential instability and the Terms of Service. Use it responsibly and understand the risks involved.