Your first design

This is the five-minute version. By the end you will have a 3D bookshelf in the viewport, you will have tweaked a slider to widen it, and you will know which button opens the export menu.

1. Open the app

Go to prompt2cad.com/app. If you are signed in (see Sign up), you land on a clean editor: chat panel on the left, 3D viewport on the right, your credit balance top-right.

2. Write your first prompt

Type in the chat input at the bottom of the left panel:

A simple oak bookshelf, 180 cm tall, 80 cm wide, 30 cm deep. Five shelves.

Hit Enter (or ⌘/Ctrl + Enter). The agent starts streaming a response.

Be concrete about dimensions and material

The more grounded your prompt is, the less back-and-forth. "An oak bookshelf 180×80×30 cm with five shelves" needs no clarifying questions; "a nice bookshelf" needs three or four.

3. Answer the clarifying questions

For anything ambiguous, the agent will show a small form inline in the chat — a few quick toggles, a number with a unit, or a "choose one" group. Pick the option that matches your intent and hit Continue. You can always type a custom answer in the Other… field.

The agent will then show you a plan: the overall dimensions, the rough internal layout, and the style direction. Skim it, hit Approve if it looks right, or paste a follow-up message asking for a change.

4. Watch the model build

Once you approve the plan, the agent writes the geometry code and the viewport renders the model live, primitive by primitive. A typical first piece takes 20–60 seconds depending on complexity. Cost: 30 credits.

When it finishes you will see a small popover near the Export button: "Your model is ready". That is the cue that the chat turn finished and the next prompt will be charged as an iteration (15 credits), not a generation (30).

5. Tweak a slider

In the bottom-right of the viewport, a small Parameters panel lists every adjustable knob the agent declared — typically width, height, depth, shelf_count, and any style enums. Drag the width slider from 80 cm to 120 cm: the model re-renders on the next frame, with the same proportions stretched to fit. No new chat turn, no credit cost.

Sliders are free

Parameter sliders re-execute the geometry code locally in your browser. They never cost credits.

6. Refine with the agent

Sliders cover small changes. For everything else, type a follow-up:

Make the bottom shelf taller for vinyl records.

The agent edits the geometry code (this costs 15 credits as an iteration) and the viewport updates with the change. You can keep iterating — add doors, change the finish, add a back panel — until you are happy.

7. Export

Click Export above the viewport. You will see:

• CAD / Engineering → STEP, DXF
• 3D / Web → GLB, DAE, OBJ, STL
• Image → PNG

PNG is free at any time. The CAD and 3D formats are gated until you top up at least once — see Top-up. The lock dialog walks you through it.

What just happened

You went through the four-stage loop the whole app is built around:

1. Prompt — natural language describing the piece.
2. Plan — the agent's interpretation, surfaced for you to approve.
3. Build — the agent writes geometry code, the viewport renders it.
4. Refine — sliders for small tweaks, follow-up prompts for everything else.

Everything from here is variations on that loop. Next: Interface tour for the layout, or jump to Writing prompts for prompt craft.