1. Core narrative rules (narrative DNA)

To keep the video engaging (“satisfaction”), the script should follow:

Single hero: One core character drives the story through action that solves the problem.
Show, don’t tell: No inner monologue; emphasize what happens on screen.
Three-part arc:
1. Opening (hook): A clear, seemingly impossible big task.
2. Middle (grind): Dense, fast execution (cathartic, orderly).
3. Ending (payoff): A strong visual reward.
Radical brevity: Voice and subtitles stay 1:1; lines only announce or briefly react—let the pictures carry meaning.

2. Technical specs and limits

Total length: $1\ \text{min}$–$3\ \text{min}$.
Segment length: Must be an integer in seconds (e.g. $4.5\text{s} \rightarrow 5\text{s}$). Diffusion clips are capped at $10\text{s}$ per segment.
Resolution: $1080\text{p}$ or $720\text{p}$.
Frame rate: $24\text{fps}$ or $30\text{fps}$.
Mandarin VO baseline: Plan copy at about 4–5 characters per second.