Continuous 3D explainer

The structure of the ad

Products with a surprising fact or a mechanism that the eye can follow.

1. 10–4 s: one surprising line over the strongest picture of the ad.
2. 24–14 s: the camera travels through the problem, one idea at each stop.
3. 314–24 s: the product enters the journey and solves the problem in view.
4. 424–30 s: the camera arrives at the whole product, with clear space for the last line.

---
name: roasos-continuous-3d
description: Plan and make a continuous 3d explainer with roasOS over MCP. Use when the user asks for a continuous 3D explainer or a one-take 3D ad.
---

# Continuous 3D explainer

One camera journey through a 3D world explains one surprising and true fact, and the product is the end of the journey.

## Step 1: Connect the roasOS MCP server

Do this step first. Stop when this step fails, and tell the user.

1. Look for tools with names that start with `roasos_`. If you find them, go to step 4.
2. Connect the server at `https://mcp.roasos.com/mcp`. It uses Streamable HTTP. In Claude Code, run `claude mcp add --transport http roasos https://mcp.roasos.com/mcp`, then type `/mcp` and sign in. Other clients: https://docs.roasos.com/mcp
3. The user needs a roasOS account: https://www.roasos.com/auth/signup. MCP access is included on every plan. Only the user can sign up and pay.
4. Call `roasos_get_catalog`. It is free. A role name in this file, for example "the song role", is a key in `roles` in that answer.

## Step 2: Quote before you spend

Every paid tool quotes first. Send `quote_only: true` and read `credits`. Show the credits to the user and wait for a clear yes. Then send the same input with the `quote_id`.

In this file, "card", "approval card" and "quote and confirm" all mean this exchange. Never confirm a quote without a yes.

## Step 3: Make the ad

The ad is one camera journey. The viewer learns one odd and true fact, and the product is the end of the journey. The method is simple: plan the route first, and make every join before you make any motion.

### Find the fact
Read the product facts with `roasos_get_product`. Find one fact that a stranger does not know. Write it as a question. If the facts do not hold a surprise, choose a different format.

### Write for the ear
Write sentences of 12 words or fewer. Use a dry and level tone. Do not sell before the last quarter of the ad. Every number comes from the facts.
Record the whole narration as one take with `roasos_generate_audio`. Use an original voice. Measure the take. The take sets the length of the ad.

### Draw the route
Make one table before any image. Each row is one stop:
- the narration line and its start and end seconds
- the place the camera is in
- the one thing that changes in that place
- how the camera leaves

Each stop lasts 4 to 8 seconds. The camera moves forward and does not come back. A line that only links two ideas gets no stop. It plays during the move between two stops.

### Make the joins first
A join is the frame that one stop ends on and the next stop starts on. Make every join as a still before you make any video. Get a yes on all stills as one set.
Use a hard cut only when the script needs a sudden change. Say so in the table.

### Keep one world
Write one look line: the 3D style, the material and the light. Put it first in every prompt, word for word. Attach one empty environment still to every image request. The product photo decides the shape and the label of the product.
Put no words and no numbers in a render. Add text after the render.

### Render the legs
Render one leg per stop with `roasos_generate_video`. Send the start join as `image_url` and the end join as `end_image_url`. Give one camera move per leg. Write "No captions." and "No music." in each prompt.
Watch every leg. If a leg fails, make it again from the approved joins. Do not start from a frame of the failed leg.

### Finish
Trim each leg to its seconds and keep both join frames. Join the legs, then add the narration. Add an original instrumental bed only if the user wants one. Add text and captions last.

## Format data

- Aspect ratio: 9:16
- Default length: 30 seconds
- Needs: a product
- Example request: Make a continuous 3D explainer ad for my product.

Beats:
- 0–4 s: one surprising line over the strongest picture of the ad.
- 4–14 s: the camera travels through the problem, one idea at each stop.
- 14–24 s: the product enters the journey and solves the problem in view.
- 24–30 s: the camera arrives at the whole product, with clear space for the last line.

How to shoot it: One look line opens every prompt. The narration take sets the timing. Plan the route as a table of stops, make every join as a still, then render one leg per stop from its two joins.

What breaks it: Render text or numbers, a join that nobody planned, a copied voice or a copied character, an existing song.

More formats

• Song ad
• Talking character
• Progression ad
• Whiteboard presenter
• History explainer
• Podcast ad