Execute Commands Inside Your Sandbox

The run_command() method executes a short-lived command inside your active sandbox container and waits for it to finish before returning the output. It’s ideal for quick, synchronous tasks such as listing files, checking Python or Node.js versions, or running lightweight scripts that complete within a few seconds. This method captures both stdout and stderr once the command completes. Because it’s optimized for speed and simplicity, run_command() has a strict 5-second execution limit and does not support streaming output.

`async run_command(cmd: str, args: Optional[List[str]] = None) -> CommandResult`

Description:
Executes a short command (< 5 seconds) and returns its standard output and standard error.
For longer-running or streaming processes, use run_streaming_command() instead.

Parameters:

Parameter	Type	Required	Description
`cmd`	`str`	Yes	Command to execute (e.g. `"python3"`, `"ls"`, `"echo"`)
`args`	`List[str]`	No	List of command arguments

Returns: CommandResult object with the following attributes:

stdout: str - Standard output
stderr: str - Standard error
exit_code: int - Exit code (defaults to 0)

Example:

import asyncio
from fermion_sandbox import Sandbox

async def main():
    sandbox = Sandbox(api_key="your-api-key")
    await sandbox.create(should_backup_filesystem=False)

    # Run a simple shell command
    result = await sandbox.run_command(cmd="pwd")

    print("Current directory:", result.stdout)
    print("Exit code:", result.exit_code)

asyncio.run(main())

Limitations:

5 second maximum : Command will timeout
No streaming - must wait for completion
Exit code is always 0 for this method (use run_streaming_command() if you need accurate exit codes)

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Execute Commands Inside Your Sandbox

`async run_command(cmd: str, args: Optional[List[str]] = None) -> CommandResult`

​async run_command(cmd: str, args: Optional[List[str]] = None) -> CommandResult

`async run_command(cmd: str, args: Optional[List[str]] = None) -> CommandResult`