In October 2025, Google changed the game. Veo 3.1 didn't just extend video length to 60 seconds—it introduced a native language for video direction: structured JSON prompting.

I remember the first night I got access to the Veo 3.1 API. I was ecstatic. I took a prompt that had worked decently in Sora and Runway—something about a neon-drenched samurai in a rainy Kyoto—and hit "Generate." The result? A flickering, inconsistent mess. The samurai’s sword turned into a baguette halfway through, and the "cinematic lighting" looked like a broken flashlight. I felt that familiar sting of AI frustration: another tool that promised the world but delivered a lottery.

Then I realized my mistake. I was talking to a director-level AI in the language of a toddler. Veo 3.1 doesn't just want a "story"; it wants a blueprint. That is where JSON (JavaScript Object Notation) comes in. It is the difference between shouting "Make it look cool!" and handing a cinematographer a shot list.

💡 Key Takeaway
  • Precision Control: JSON eliminates the ambiguity of text prompts by separating style, camera movement, and action into distinct, machine-readable blocks.
  • Temporal Coherence: Using the continuity block ensures characters and props remain stable across the full 60-second generation.
  • Native Audio Sync: JSON allows for millisecond-precision timing between visual actions and generated sound effects or dialogue.

Why Veo 3.1 Demands JSON (Not Just Text)

Veo 3.1's architecture is built on atomic scene processing. Unlike earlier models that try to "hallucinate" an entire video from one paragraph, Veo 3.1 parses information based on front-loaded token weighting. In plain English: the first things you say matter most, but in a long text prompt, the AI often "forgets" the ending.

The "Ingredients to Video" feature is the heart of this update. It allows you to feed the model specific references—images, style presets, and even audio cues. When you use a standard text prompt, you're basically tossing all those ingredients into a blender. JSON, however, acts as a gourmet recipe, telling the model exactly when to use the "lighting" ingredient and how to apply the "camera" spice.

Comparison: Text Prompt vs. JSON Prompt

Feature Text Prompting JSON Structured Prompting
Consistency High risk of "morphing" Locked via continuity blocks
Camera Control Suggestions (often ignored) Mandatory parameters (highly adherent)
Audio Random ambient noise Precisely timed sound events
Efficiency High "credit waste" on bad seeds Higher first-time success rate

The Anatomy of a Veo 3.1 JSON Prompt

JSON prompting is the process of organizing your creative intent into a hierarchical data structure that the Veo Flow editor can parse without error.

The Essential Schema

  1. output: Defines the "canvas" (resolution, aspect ratio, and the full 60s duration).
  2. global_style: The "DNA" of the video—mood, color grading, and safety filters.
  3. continuity: This is the secret sauce. You define your "Character Bible" here so the AI remembers what your lead looks like in Scene 10.
  4. scenes[]: An array of individual shots. Veo thrives on the "one action per scene" rule.
  5. audio: Specific cues for SFX and ambient layers.
cyberpunk_chase.json 
{
  "version": "veo-3.1",
  "output": {
    "duration": "15s",
    "resolution": "4k",
    "aspect_ratio": "21:9"
  },
  "global_style": {
    "look": "Anamorphic Cinematic",
    "mood": "Tense/High-Stakes",
    "color_grading": "Cyberpunk Teal and Orange"
  },
  "continuity": {
    "characters": [{ "id": "hero_1", "description": "Woman in chrome jacket, glowing blue eyes" }]
  },
  "scenes": [
    {
      "id": "shot_01",
      "timestamp": "00:00-00:05",
      "shot": {
        "type": "Low Angle Tracking",
        "camera": "Dolly In"
      },
      "action": "hero_1 sprints through a crowded neon market, splashing through puddles.",
      "audio": { "sfx": "Heavy rhythmic footsteps, splashing water, neon hum" }
    }
  ]
}

Beginner Workflows – Building Your First JSON

When I started, I tried to write these by hand in VS Code. It was a nightmare. One missing comma and the whole generation would fail, eating up my time and patience.

The Workflow:
  1. Concept: Start with a simple idea. "A cat drinking milk."
  2. Breakdown: Don't just say "drinking milk." Think: Close-up shot? Soft morning light? Cinematic 4k?
  3. Structure: Assign these to the JSON fields.

(Pro tip: Veo weights the first 10 tokens heavily—always lead your action string with the most important visual element).

This is where our JSON Prompt Generator PWA (currently in free Beta!) becomes a lifesaver. Instead of worrying about syntax, the tool provides a visual interface. You select "Close-up" from a dropdown, and it writes the "shot": {"type": "Close-up"} code for you. It automates the "boring" technical part so you can focus on being a director.

Pro Techniques for Cinematic Control

Advanced Camera Grammar

Veo 3.1 understands sophisticated cinematography, but only if you use the right terms in the shot block.

  • Dolly Zoom (The "Vertigo" Effect): Set camera_movement to forward while specifying a focal_length shift in the action description.
  • Dutch Angle: Use this in the global_parameters to create a sense of unease throughout the sequence.

Scene Atomicity & Shot Continuity

The biggest "pro" secret? Scene Atomicity. If you want a 30-second video, don't write one long scene. Write six 5-second scenes. By using the Atomic Scene Locks in our PWA tool, you can ensure that the lighting in Scene 1 perfectly matches Scene 2, preventing that jarring "AI jump" between shots.

Term Effect
Orbit Circular movement around a subject
Crane Shot Vertical movement (up or down)
Pan/Tilt Horizontal or vertical rotation
Tracking Following a subject at a constant distance

Troubleshooting & Optimization

Professional Troubleshooting Guide
  • "Veo ignores my camera instructions": You’re likely "burying the lead." Move your camera keywords to the very beginning of the action field or ensure the shot block is correctly defined.
  • "Character morphs between scenes": You aren't utilizing the continuity block. You need to define a Character Bible. Our tool’s "Character Bible Lite" feature lets you upload a reference image, which the PWA then converts into a permanent JSON reference ID for every scene.
  • "Audio is out of sync": Ensure your audio timestamps match your scene timestamps exactly. If a glass breaks at 00:04.5, your SFX cue must be precisely at that mark.

Why Use the JSON Prompt Generator?

Look, you can write JSON manually. But as someone who spent three hours debugging a single bracket, I don’t recommend it.

Our JSON Prompt Generator PWA (Free during Beta) was designed to bridge the gap between "I have a cool idea" and "I have a perfectly formatted JSON file."

🚀 Tool Features:
  • Visual Scene Builder: Drag and drop scenes to reorder your timeline.
  • Cinematic Dictionary: Access over 100+ professional terms for lighting and mood.
  • Cost Calculator: Real-time token estimation so you don't blow your API budget.
  • One-Click Export: Get your JSON ready for Google Flow or Vertex AI instantly.

Manual JSON creation takes roughly 30 minutes for a complex sequence. With the tool, I’ve gotten it down to under 3 minutes.

Ready to stop guessing and start directing?

Try the Veo-Ready JSON Generator in our JSON Prompt Generator for 100% Free while we are still in Beta. I can't wait to see what you build.

Try it Now →

Conclusion

JSON isn't just a formatting choice—it’s the steering wheel for the most powerful video AI Google has ever built. By mastering the structure of Veo 3.1, you transition from someone who hopes for a good result to someone who engineers one.

The future of video is structured. Whether you’re building a 5-second social clip or a 60-second cinematic masterpiece, your success depends on the clarity of your blueprint.

Would you like me to generate a specific JSON template for a particular scene you're working on?