The Recipe: your piece's readable history

A Recipe is the list of steps that builds one piece, in order. If you know other CAD tools, it is the feature tree, but written as sentences you can read aloud.

1. Sketch on the XY plane: rounded rectangle 80 by 50 mm, corner radius 4 mm
2. Extrude the sketch 12 mm
3. Shell the part, open the top face, wall 2 mm
4. Add 4 heat-set bosses for M3 in the corners
5. Fillet the outer vertical edges, radius 3 mm

Each step has tappable values. Change "12 mm" to "20 mm" and everything after it rebuilds.

Why a Recipe instead of just a shape

A shape tells you what exists. A Recipe tells you how it came to be, and that is what makes changes safe:

• You can change the early decisions (the width) without redoing the late ones (the fillets).
• Someone else, or you in six months, can understand the model in a minute.
• The agent works in Recipe steps, so every action it takes is visible and reversible.

What kinds of steps exist

You do not need to memorize these, but it helps to recognize them:

Smart features

Some steps are smart features, bundles of geometry for common maker needs. They expand into real geometry, but appear in the Recipe as one readable step:

• Screw boss and heat-set boss
• Standoff
• Vent slots
• Snap hook
• Lid lip (a lip and groove for a lid)
• Text emboss and text engrave
• Spur gear
• Hinge knuckle
• USB-C cutout
• Cable hole
• Keyhole mount
• Countersunk mount holes

When you say "add vent slots on the back", the agent will often reach for one of these, so you get tidy parameters instead of 30 hand-drawn cuts.

Working with the Recipe

Read it

Scan top to bottom. The Recipe is ordered, and later steps build on earlier ones. A step labeled with the agent as its author was proposed by the agent. Some steps carry a short note explaining why.

Edit values

Tap a value inside a step and change it. You can type a number or a formula that uses your Parameters (wall * 2 + 0.3).

Suppress instead of delete

Switch a step off (suppress it) to see the model without it. The step stays in the history, so you can switch it back on. The agent works this way too: it never deletes history, it suppresses.

Reorder carefully

Steps can be moved, but order matters. A fillet applied before a hole behaves differently from one applied after. If a move breaks something, the step turns red and explains why (see A step turned red after I changed a parameter).

Replay it

Build replay lets you scrub through how the piece was built, step by step. For agent steps, teaching mode can replay slowly with the reasons attached.

Read it in code

Every piece is also available as readable code in script view, and you can edit either side. It is aimed at professionals who prefer text.

What the Recipe does not store

The Recipe never stores "face number 17" or "edge number 42". It describes selections by meaning, such as "the edges of the top face" or "cylindrical holes with radius 1.5 mm". That is why a Recipe survives upstream changes far better than index-based tools. The article Selectors and topological naming explains this for professionals.

Recipe, Parameters, and Design intent

These three work as a team:

Try it

Open any template and ask:

The agent answers by reading the Recipe and pointing at the steps and parameters that control width.