Run Code Skill
Author a small program and run it. This is the "code-execution-as-action" primitive: rather than being limited to a fixed catalog of tools, the agent can write a throwaway script to do exactly what a task needs and execute it.
When to Use
Reach for run_code over bash when the task is really a small program:
- Data transforms: parse JSON/CSV, reshape, aggregate, filter
- Math / computation: anything beyond a one-liner
- Using a library: call a python or node module to do the heavy lifting
- Generating a tool on the fly: write the logic once, run it, read the result
For a single shell command (ls, git status, npm install), use bash.
Input
json{ "language": "python", "code": "import json\nprint(json.dumps({'sum': sum(range(10))}))", "timeout": 60000 }
| Parameter | Type | Required | Default | Description |
|---|---|---|---|---|
language | string | Yes | - | python, javascript, or bash |
code | string | Yes | - | Full program source; print results to stdout |
timeout | number | No | 60000 | Timeout in ms (max 120000) |
Output
json{ "success": true, "output": "{\"sum\": 45}\n", "error": "", "exitCode": 0, "language": "python" }
| Field | Type | Description |
|---|---|---|
success | boolean | True if the program exited 0 |
output | string | Captured stdout |
error | string | Captured stderr (or error message) |
exitCode | number | Process exit code |
Notes
- The program runs in the workspace directory; temp source files are written to the OS temp dir and cleaned up after execution.
pythonrequirespython3on PATH; if it's missing, the result explains how to install it.javascriptruns undernode.bashruns underbash.- Output is captured up to 1 MB; long-running programs are killed at the timeout.
- Same trust model as the
bashskill: it runs on the host unless the operator enabledSANDBOX_MODE, in which case writes outside the workspace (and, if configured, network access) are denied.


