Short answer: put the story in the prompt and leave the look to the settings. A good prompt says who or what it is about, what actually happens, and who it is for. It does not say what style to draw it in, how long to make it, what language to speak or what shape to export, because those are separate controls and writing them into the prompt usually makes the result worse, not better.

The mistake almost everyone makes

Most first prompts look like this: “make a 30 second vertical cartoon video in English about coffee with upbeat music”. Five instructions, and four of them belong somewhere else. The generator now has to work out which words are the subject and which are production notes, and it often guesses wrong. You end up with a video that is about cartoons and vertical formats as much as it is about coffee.

Strip it back to “How coffee went from a wild berry in Ethiopia to the second most traded commodity on earth” and set the style, length, language and shape in the controls. You will get a better video and you will be able to change the look without rewriting the idea.

What goes where

The four things a good prompt has

1. A subject, stated plainly

Not a category. “Productivity” is a category. “Why Parkinson’s Law means work expands to fill the time you give it” is a subject. The narrower it is, the less the generator has to invent.

2. What actually happens

A video is a sequence. If your prompt has no sequence in it, the generator writes one, and it will be a generic one. Say what the beginning, middle and end are, even roughly: a problem then a cause then a fix, or a before then a turning point then an after.

3. Who it is for

“For people who have never traded before” and “for portfolio managers” produce very different scripts from the same subject. One line is enough.

4. Anything you would be annoyed to see missing

If the video must mention your product, a specific figure, a named place or a particular objection, say so. The generator will not guess what matters to you.

One sentence versus five

One sentence works, and it is the fastest way to see whether the idea has legs. You will get a reasonable structure and generic examples. Five sentences gets you a video closer to what was in your head, because you have made the decisions instead of leaving them to the machine.

There is a point of diminishing returns. Past roughly 150 words you are writing a script, not a prompt, and you would be better off pasting the actual script into the script field where it will be used verbatim rather than interpreted.

Controlling the length

This is the most common follow-up question and the answer is not what people expect. Asking for “a 45 second video” in the prompt rarely works, because length is a function of how much narration there is, and narration is a function of how much you asked for. If you want it short, give it less to say: one idea, not five. If you want it long, give it a sequence with more steps in it. Where the tool has a length or scene count setting, use that instead of asking in words.

Naming your characters

If the same person appears more than once, name them in the prompt and describe them once. “Maya, a 42 year old shopkeeper in Jaipur” told once at the start is worth more than mentioning her in every scene. Tools that draw a reference sheet per character will use that description to keep her consistent from the first scene to the last; tools that do not will redraw her each time whatever you write.

What to leave out

Four things that usually hurt. Camera directions, unless the tool explicitly takes them, because they get read as subject matter. Style words like cinematic or cartoon, which fight with the style setting. Resolution and format, which are export options. And negative instructions, as in “no text on screen”, which many models handle poorly and which belong in settings where they exist.

Weak and strong, side by side

Weak: “a video about our product”

Strong: “How a small clinic cut no-shows by sending automated reminders. Start with the receptionist chasing people by phone, show the switch, end with an empty waiting-room queue. For practice managers who are not technical.”

Weak: “bedtime story”

Strong: “A rabbit called Pip who is afraid of the dark finds out the moon has been watching over him all along. Gentle, three short scenes, ends with him asleep.”

Weak: “explain compound interest”

Strong: “Why 100 rupees saved at 20 beats 1,000 rupees saved at 40. Show the two savers side by side, the gap opening over thirty years, and the one number that explains it. For first-time earners.”

Questions people ask

Can I generate a video from a prompt for free?

Yes. There is a free tier, usually limited by length or watermark, which is enough to test whether your prompt produces what you expected before paying for anything.

How long should a prompt be?

One to five sentences. Below one you are leaving everything to the machine; above about 150 words you have written a script and should paste it as a script instead.

Can I ask for a specific number of seconds?

You can ask, but length follows from how much narration there is. Control it by giving the generator more or less to say, or by using the length setting where one exists.

Will it add a voiceover automatically?

Yes. The narration is written from the prompt and spoken, with subtitles laid on. You choose the language separately rather than asking for it in the prompt.

Can I edit it afterwards if the prompt was not quite right?

On a tool that gives you an editable timeline, yes, and that matters more than getting the prompt perfect first time. Regenerating one scene is quicker than rewriting the prompt and starting over.

Try a prompt and see what comes back

The fastest way to learn what a generator does with your words is to give it one sentence and look at the scene list before you watch the video. Write one sentence and generate a video, free to start.