# Walkthrough: a DGX Spark

A worked example - model an NVIDIA DGX Spark from your photos with Claude Code, check it face by face, and publish it.

Source: https://rack-maker.cbnsndwch.dev/docs/agents/walkthrough

## What you need

- Claude Code installed, and a Rack Maker account.
- The device, and a phone or camera.
- Its datasheet's URL, if it has one.

The same steps work with any MCP client; only the connecting differs. See [Connecting your client](https://rack-maker.cbnsndwch.dev/docs/agents#connecting-your-client).

### Connect Claude Code

Add the server:

```bash
claude mcp add --transport http rack-maker https://rack-maker.cbnsndwch.dev/mcp
```

Start `claude` and run `/mcp`, pick `rack-maker`, and sign in. Your browser opens Rack Maker: sign in there if you aren't already, then choose **Allow**.

![The page that opens to sign your agent in: Allow Claude to model devices as @ana, with Allow and Cancel](https://rack-maker.cbnsndwch.dev/docs/shots/agents/consent-light.webp)

*Choose Allow.*

### Take the photos

Put straight-on photos of the Spark's faces in a folder, such as `~/spark`: the front, the rear and the sides. A ruler or calipers in view helps the agent check its numbers.

The photos stay in that folder. The agent reads them there and sends Rack Maker only numbers.

### Ask

Tell the agent what you know, and how you want it to work:

> Model my NVIDIA DGX Spark from the photos in \~/spark. It is 150 × 150 × 50.5 mm. Keep the datasheet at (its URL) with it. Mark what you measured, and show me each face before you save.

### Watch it work

The agent:

1. creates the draft (`create_draft`);
2. sets the body's size;
3. traces each photo: it sends the photo's size and the face's corners on it (`setPhoto`, `setCorners`), then turns the centre of each opening into millimetres on the face (`image_to_face`);
4. places the ports, marking them as measured;
5. keeps the datasheet with the device (`attach_datasheet`);
6. draws each face (`render_faces`), compares each drawing with your photo, and corrects what differs.

If you have the modeler open on the draft, you see each change as it happens.

### Check it in the modeler

Open the link the agent gives you, such as `/catalog/model/<your-handle>/dgx-spark/1`, to see the draft in the modeler, in 3D. Ask the agent for changes, or make them yourself there: your edits reach the agent too.

![A DGX Spark modelled by an agent, open in the modeler on its rear face](https://rack-maker.cbnsndwch.dev/docs/shots/agents/agent-draft-light.webp)

*The agent's draft in the modeler.*

### Publish

When you are happy, ask the agent to publish. With contributor access, the Spark is published at once with its model file, which the server builds from the measurements. Without it, the Spark is submitted for review, and an admin publishes it. See [Publishing](https://rack-maker.cbnsndwch.dev/docs/modeler/publishing).

## Tips

- **Give it the known sizes.** The overall size from the box or the datasheet anchors everything else.
- **Straight-on photos** give the best numbers. The agent corrects for a slight angle, not a steep one.
- **Ask it to show you the faces.** `render_faces` draws each face as seen from outside, like your photo, with every port named.
- **Ask it to mark sources.** Measured, datasheet or estimated: the review counts them.

To see the conventions the agent follows, read [How an agent measures](https://rack-maker.cbnsndwch.dev/docs/agents/measuring).