title: Custom Code Tool node documentation
description: >-
Learn how to use the Custom Code Tool node in n8n. Follow technical
documentation to integrate Custom Code Tool node into your workflows.
contentType:
- integration
- reference
priority: high
Custom Code Tool node
Use the Custom Code Tool node to write code that an agent can run.
On this page, you'll find the node parameters for the Custom Code Tool node and links to more resources.
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Node parameters
Description
Give your custom code a description. This tells the agent when to use this tool. For example:
Call this tool to get a random color. The input should be a string with comma separated names of colors to exclude.
Language
You can use JavaScript or Python.
JavaScript / Python box
Write the code here.
You can access the tool input using query. For example, to take the input string and lowercase it:
let myString = query;
return myString.toLowerCase();
Templates and examples
[[ templatesWidget(page.title, 'code-tool') ]]
Related resources
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