# MiniMax H3 brushing prompt: reveal a clean track only behind the bristles

Move a brush once across a dusty panel and leave a narrow cleared track behind its contact area. The task links a tool's path to a persistent local surface change.

Original synthetic practice still, not a generated result. No model run has been performed.

Files: first-frame.png (1024×1024 actual first-frame input), first-frame.svg (editable geometric design source; do not upload as if it were PNG), prompt.en.txt / prompt.zh.txt, acceptance.blank.csv (all observations empty), task-definition.json and RIGHTS-REVIEW.txt.

## Generator

Use MiniMax H3 base image-to-video. Turn on Add end frame to expose First Frame, upload first-frame.png only, and leave Last Frame empty. Fast requires a pair and is not covered. Choose only options offered by the current interface; opening it does not submit.

## Starting state

The original overhead drawing has a framed panel with sparse dark dust dots. A broad brush touches its left half; a small clean patch is already visible immediately behind the bristles. Nothing represents a real cleaning product or a before-and-after performance claim.

Fix the panel corners and follow the leading bristle edge. The cleared region must trail that edge rather than appear ahead of it or clear the entire panel at once.

## Steps

1. Locate the existing clean patch and the brush's contact edge. A clear starting relationship makes the direction of cause and effect inspectable.
2. Ask for a single straight pass, not a sparkling product reveal. Keep liquid and dust clouds out of the first attempt so the trail is easy to compare.
3. Pause before motion, halfway along the pass and at the end. Look at untouched dots ahead and outside the band as well as the newly cleared surface behind.

## Acceptance

- The panel's border remains fixed and the brush stays singular.
- The clean band grows only where the bristles have already passed.
- Dust ahead of and outside the brush path remains visible.
- The clean track persists in the final hold rather than refilling immediately.

## Limits

This is a synthetic visual continuity task. It does not measure dust removal, cleaning efficacy, bristle mechanics or a real product result.

Read prompt.en.txt before submitting. No pass results or output video are included.