> ## Documentation Index
> Fetch the complete documentation index at: https://docs.firstresonance.io/llms.txt
> Use this file to discover all available pages before exploring further.

# Manage tool models

> Create tool models in the Tools Library, categorize them with subtypes, set maintenance intervals, revise them, and delete them.

You manage [tool models](/build-hardware/tools/overview) in the **Tools Library**: in the **Supply Chain** section of the sidebar, click **Tools Library**.

## Create a tool model

1. On the **Tools Library** page, click **Create Tool**.
2. Enter a **Tool Number** and **Revision** (both required).
3. Optionally add a **Description**, one or more **Subtypes**, and a **Maintenance Interval**.
4. Click **Create Tool**.

ION opens the new tool model's detail page.

## Categorize tools with subtypes

Add [subtypes](/build-hardware/tools/overview#subtypes) in the **Subtypes** field when you create a tool model or from the tool model's detail page; type a name and select an existing subtype, or create a new one on the spot.

## Set a maintenance interval

Enter the [maintenance interval](/build-hardware/tools/overview#maintenance-interval-and-status) as a list of `{number}{unit}` segments using this shorthand:

| Shorthand | Unit   |
| --------- | ------ |
| `d`       | Day    |
| `h`       | Hour   |
| `m`       | Minute |

For example, `1d 2h 20m` is an interval of 1 day, 2 hours, and 20 minutes.

## Edit a tool model

Open a tool model from the Tools Library to reach its detail page. Fields in the **Tool Information** card edit in place and save automatically, including subtypes and any custom attributes.

* To revise the model, click **Create New Revision**. ION creates the next revision and opens it.
* To remove the model, open the **...** menu and click **Delete**. Deletion can't be undone.

## Related

* [Manage tool inventory](/build-hardware/tools/manage-tool-inventory)
* [Record tool usage on a run](/build-hardware/tools/record-tool-usage)
* [Manage parts](/build-hardware/parts/creating-managing)