From Script to AI Video: A Step-by-Step Workflow with Claude or ChatGPT, Then Grok, Google Flow, or Higgsfield

Most people who try AI video start in the wrong place. They open a video generator, type one long sentence, and get a clip that looks nice but goes nowhere. The better route starts earlier: with a script, a shot list, and one clear prompt per shot. Only then do you open the video tool.

This guide walks through that route in eight steps. A text assistant such as Claude or ChatGPT does the planning and writing. Then you generate the clips in Grok Imagine, Google Flow, or Higgsfield. I read each tool’s own help or developer pages for the numbers below, and I mark the places where I could not confirm a detail.

Limits and prices in this field change quickly. Treat every number as a snapshot and check it in the app before you budget.

The Workflow at a Glance

1. Decide what the video is for
2. Write the script
3. Split the script into shots
4. Turn each shot into a video prompt
5. Make reference images so characters stay consistent
6. Generate the clips
7. Add voice and sound
8. Review, fix, and assemble

Step 1: Decide What the Video Is For

Before you ask any AI for anything, write down four things: the goal, the platform, the length, and the aspect ratio. A 30-second vertical clip for social media needs a different plan from a 3-minute horizontal explainer.

Length matters more than people expect. Most AI video tools produce short clips, so a longer video is really a sequence of many short ones. The Grok developer documentation, for example, lists generation of up to 15 seconds per video. A 60-second video therefore needs at least four clips, and realistically more, because some will fail.

Step 2: Write the Script with Claude or ChatGPT

Either assistant can draft the script. What matters is the brief you give it. Include the audience, the goal, the total length, the tone, and a rule that the script must be easy to show visually.

Here is a prompt you can adapt:

Write a 45-second script for a vertical video aimed at small-business owners. Goal: explain why customers abandon online carts. Tone: friendly and direct. Use short sentences. For each line, add a short note on what the viewer should see on screen. Do not include any real brand names or real people.

The last sentence is a safety habit: it keeps the visuals generic, so you are not asking a video model to recreate a real brand or a real person’s face.

Read the result aloud. A script that sounds awkward when spoken will sound worse in a synthetic voice. Ask the assistant to trim, simplify, and cut any line that does not earn its place.

Step 3: Split the Script into Shots

A video model makes one clip at a time, so ask your assistant to convert the script into a shot list. A table works well:

Keep each shot to one action. If a shot contains two actions, split it. Models handle a single clear movement far better than a sequence of events.

Step 4: Turn Each Shot into a Video Prompt

This is the step that decides quality. Google’s Flow help page recommends a detailed prompt covering the subject, action, environment, lighting, and style. That list is a solid skeleton for any tool. Add the camera movement and you have a repeatable formula:

Subject + action + setting + lighting + camera + style

Ask your assistant to rewrite every row of the shot list in this format. Example for shot 1:

A woman in her thirties sits at a wooden kitchen table, closes her laptop slowly and sighs. Morning light from a window on the left. The camera pushes in slowly. Natural, realistic style, shallow depth of field.

Ask the assistant to keep a short “style line” and reuse it word for word in every prompt. Identical style language is one of the cheapest ways to make separate clips look like they belong together.

Step 5: Make Reference Images for Consistency

The biggest weakness of AI video is that a character can look different from one clip to the next. The fix is to start from images instead of from text alone.

Generate or upload a reference image of each main character and location first. Our guide to free AI image generators compares tools for this. Then feed those images into the video tool, where each platform handles them differently:

• Google Flow offers “Frames” (a start frame, an end frame, or both) and “Ingredients” (reference images or videos). Flow’s help page says plain or segmented backgrounds work best for subject references.
• Grok supports image-to-video, and the developer documentation says the 1.5 model accepts up to 14 reference images and pinned first, last, and mid-video frames.
• Higgsfield lets you upload a reference image if the model you pick supports one.

Step 6: Generate the Clips

Google Flow

Flow’s help page lists the steps for the standard prompt box:

1. Open Flow and start a project.
2. Enter your detailed prompt.
3. Click the model name and choose Video.
4. Optionally add ingredients or frames.
5. Set aspect ratio, number of outputs, model, and generation length.
6. Click Generate.

There is also an Agent mode, where you describe the scene, optionally drag in media, and ask for several variations at once.

Credits. According to Google’s credits page, people without a subscription get 50 credits per day, AI Plus gets 200 per month, AI Pro gets 1,000 per month, and the two Ultra tiers get 10,000 and 25,000. Example costs: Veo 3.1 Lite is 10 credits for non-Ultra subscribers, and Veo 3.1 Fast is 20 credits. By that arithmetic, 50 daily credits cover about two Fast generations, and AI Pro’s 1,000 monthly credits cover about 50. The page does not say which models free accounts can use, and it warns that people without a subscription may be unable to generate video during peak hours, roughly 2 PM to 5 PM UTC.

Audio. The help page covers audio only through voice references: a single-speaker voice for ingredient-based videos, using the Omni Flash model.

Best for: people who want an all-in-one workspace from prompt to scene.

Watch out for: availability can differ by country, and credit costs can change.

Grok Imagine

The consumer experience lives at grok.com/imagine, which describes animating images into videos. I could not confirm current consumer limits. The only detailed source I found was a third-party page from September 2025, which is too old to rely on, so check what your plan allows inside the app.

The xAI developer documentation is clearer, and it matters if you build your own pipeline. It states that Grok Imagine video supports text-to-video and image-to-video, durations up to 15 seconds, resolutions of 480p, 720p, and 1080p, and lip-synced speech. Pricing is per second: the 1.5 model starts at $0.08 per second and the 1.5-lite model at $0.02 per second, with duration and resolution affecting the final cost. At those starting rates, a 10-second clip costs about $0.80 on 1.5 and about $0.20 on 1.5-lite, before any resolution premium. Requests are asynchronous: you submit one and check back until it finishes.

Best for: quick image-to-video clips with speech, and developers who want an API.

Watch out for: consumer limits that I could not verify, and per-second pricing that grows fast on long clips.

Higgsfield

Higgsfield is different: it is a hub rather than a single model. Its help center lists models including Veo 3.1, Kling 3.0, Sora 2, WAN 2.6, Seedance 2.0 and 2.5, and Grok Imagine 1.5. That makes it useful for testing the same prompt on several models side by side.

The first-generation guide gives the steps: choose Image or Video, pick a model, enter a prompt, upload a reference image if the model supports one, adjust duration, aspect ratio, or resolution, and click Generate.

Credits. According to Higgsfield’s credits page, the cost depends on the model, resolution, and duration, and it appears on the Generate button before you confirm. Subscription credits expire at renewal and do not roll over, while purchased credit packs expire after 90 days. The plans page says you can generate without a paid plan, but access is limited to a small set of models and includes no credits. I did not find plan prices on a page I could read, so check the pricing page.

Best for: comparing several video models in one place.

Watch out for: credits vanish at renewal, and the price varies by model.

Quick Comparison

Step 7: Add Voice and Sound

You have three practical options. First, use the built-in audio: Flow supports voice references with certain models, and Grok’s documentation mentions lip-synced speech. Second, generate narration separately with a text-to-speech tool and lay it over silent clips. Third, record your own voice, which is often the most believable choice and costs nothing.

Whichever route you pick, use the script from Step 2 as the single source of truth, so the words and the visuals stay matched.

Step 8: Review, Fix, and Assemble

Plan on generating more than you need. Expect some clips to have odd hands, drifting faces, or text that is unreadable. For each shot, generate a few variations and keep the best.

Then assemble the clips in any video editor, add your narration, trim to the beat of the script, and export. Keep the cuts tight: short AI clips feel more natural when you cut away before the model’s weaknesses show.

Finally, check each platform’s rules on labeling AI-generated content before you publish, and avoid using real people’s faces or voices without permission.

Common Mistakes to Avoid

Starting in the video tool. Without a script and shot list, you will burn credits on clips you cannot use.

Packing several actions into one shot. Split them into separate clips.

Changing the style language between prompts. Reuse the same style line.

Skipping reference images. Characters will drift from clip to clip.

Ignoring cost until the end. Check the credit or per-second price before you generate a batch.

Trusting audio blindly. Listen to every generated voice line for mistakes.

Frequently Asked Questions

Should I use Claude or ChatGPT for the script? Either works. Give both the same detailed brief and keep whichever draft reads better aloud.

Which video tool is best for beginners? Flow gives a guided workspace with frames and ingredients. Higgsfield is easiest for comparing models. Grok is the quickest for turning one image into a clip.

How long can an AI video clip be? It depends on the tool and model. Grok’s developer documentation lists up to 15 seconds per video, and longer videos are built by joining clips.

Can I make a full video for free? You can try each tool for free, but the limits are tight: Flow gives 50 daily credits to non-subscribers, and Higgsfield’s free access covers only a small set of models without credits.

How do I keep a character consistent? Start from a reference image and reuse the same description in every prompt.

The Bottom Line

The tool matters less than the process. Write the script first, break it into one-action shots, turn each into a prompt with the same formula, and generate from reference images. Use Flow if you want a single workspace, Grok if you want fast image-to-video, and Higgsfield if you want to compare models. If your video is for YouTube, our guide to free AI tools for YouTube creators covers scripts, thumbnails, and captions.

Sources

• Google Flow Help: create videos in Flow
• Google Flow Help: manage your Flow credits
• xAI docs: video generation
• Grok Imagine
• Higgsfield help: how do I create my first generation
• Higgsfield help: how credits work
• Higgsfield help: how plans work