Run Code UI

The code left sidebar icon opens a scratch pad for running stand-alone Python, JavaScript, TypeScript, and C# code in a sandbox.

The UI uses CodeMirror as the code editor, providing a better user experience with syntax highlighting, code completion, and other IDE-like features for writing code.

Run Python

Run JavaScript

Run TypeScript

Run C#

These make use of the following core tools:

• run_python(code) - Executes Python code.
• run_javascript(code) - Executes JavaScript code (uses bun or node).
• run_typescript(code) - Executes TypeScript code (uses bun or node).
• run_csharp(code) - Executes C# code (uses dotnet run with .NET 10+ single-file support).

These tools allow LLMs to run code snippets dynamically as part of their reasoning process.

Python and C# Examples

Run Python

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Run C#

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JavaScript and TypeScript Examples

Run JavaScript

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Run TypeScript

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Sandbox Environment

Code execution happens in a temporary, restricted environment to ensure safety and stability.

Resource Limits

To prevent infinite loops or excessive resource consumption, the following limits are enforced using ulimit (on Linux/macOS):

• Execution Time: The process is limited to 5 seconds of CPU time.
• Memory: The process is limited to 8 GB virtual memory limit.

File System

• Each execution runs in a clean, temporary directory.
• Converting LLMS_RUN_AS will try to chmod 777 this directory so the target user can write to it.
• Note: Files created during execution are transient and lost after the tool completes, unless their content is printed to stdout.

Environment Variables

• The environment is cleared to prevent leakage of sensitive tokens or API keys.
• Only the PATH variable is preserved to ensure standard tools function correctly.
• For C# (dotnet), HOME and DOTNET_CLI_HOME are set to the temporary directory to allow write access for the runtime intermediate files.

Running with Lower Privileges (LLMS_RUN_AS)

By default, code runs as the user running the LLMS process. For enhanced security, you can configure the tools to execute code as a restricted user (e.g., nobody or a dedicated restricted user).

Configuration

Set the LLMS_RUN_AS environment variable to the username you want code to run as.

Example:

export LLMS_RUN_AS=nobody

Requirements for LLMS_RUN_AS

1. Sudo Access: The user running the LLMS process must have sudo privileges configured to run commands as the target user without a password.
2. Permissions: The LLMS process attempts to grant read/write access to the temporary execution directory for the target user (via chmod 777).

Example sudoers configuration:

# Allow 'mythz' to run commands as 'nobody' without password
mythz ALL=(nobody) NOPASSWD: ALL

How it Works

When LLMS_RUN_AS is set:

1. A temporary directory is created.
2. Permissions on the directory are relaxed so the restricted user can access it.
3. The command is executed wrapped in sudo -u <user>.
   • Example: sudo -u nobody bash -c 'ulimit -t 5; ... python script.py'

This execution model ensures that even if malicious code escapes the ulimit sandbox or accesses the filesystem, it is restricted by the OS-level permissions of the nobody (or specified) user.