explain-with-anim

The user asked a question. Answer it with a picture and the words that walk the picture — not a picture instead of an answer, and not a paragraph with a decorative diagram after it. The figure is drawn from the code (or the facts) by vlmkit-anim, checked, and delivered as a file; the prose follows the figure beat by beat and names the things in it by their ids.

Read explanatory-animation for how to write and check a scene. This skill is about what to draw, from what, and how to explain with it.

First: does a picture help?

Draw when the answer has things and relations — four or more modules, states, participants, steps — or an order in time, or a before and after. Do not draw for a one-line answer, a single function's body, or a question about a value. If in doubt, write the answer first; if it needs a list of more than four named things that point at each other, draw them.