The Canvas Chat: Building an Ad by Describing It

Most of Gendia asks you to know what you want. The Canvas chat asks you what you're selling, and works the rest out with you.

It isn't a chatbot that makes pictures. It's an agent with a specific job, build a multi-scene ad, and a fixed set of moves it can make to get there.

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The plan card, which is the important part

Before anything is generated, the agent opens a plan card: what it's going to make, how many scenes, in what shape.

Nothing is billed until you confirm it.

That's the single most important thing about this feature, and the reason it's safe to be vague at the start. You can describe a half-formed idea, watch it turn into a concrete plan, and then decide whether that plan is worth paying for. If it isn't, change it or walk away, you've spent nothing.

Read the card properly. It's the cheap moment.

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What the agent can actually do

Thirteen moves, and knowing them tells you what to ask for:

Setting up

• start_ad, opens the project and the plan card
• update_brief, changes the concept without starting over
• set_scene_count, between 1 and 6 scenes

Casting

• cast_model, generates human model candidates when the ad needs a person
• select_model_candidate: you pick one
• regenerate_model, none of them are right, try again
• skip_model: no people in this ad

Making it

• generate_scenes: the scene stills
• reroll_scene: one scene again, leaving the others alone
• update_scene, change a scene by describing the change
• render_video, turn the stills into video, as a separate step

Steering

• ask_user: it asks you when something required is genuinely missing
• go_back_to, return to an earlier stage without losing the project

reroll_scene and update_scene are the two worth remembering. When one scene of five is wrong, you fix that scene. You don't regenerate the ad.

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How to open

The agent is told not to ask about style or mood before it understands what is being advertised. So lead with that:

"An ad for our cold brew coffee: the can, on a kitchen counter, summer morning."

Then let it ask. What actually helps up front:

• A product photo. Attach it. This is the difference between an ad for your can and an ad for a can.
• A scene count, if you have one. Otherwise it decides.
• Whether you want a person in it. Say "no people" and it skips casting entirely.
• The shape, 16:9, 9:16 or 1:1.
• Images or video. If the stills are the deliverable, say so and skip the video step.

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Casting

If the ad wants a person, the agent generates candidates and you choose. You can regenerate the set if none fit, or skip it.

Worth doing deliberately: the model you pick carries across every scene, so a candidate that only half works in the first scene will half work in all six.

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Scenes first, video second

The order is deliberate and it's the same economy as everywhere else on Gendia: stills are cheap, video is not.

Scenes are generated as images. You look at them, reroll the ones that miss, update the ones that are close. Only when the storyboard is right does render_video turn them into footage.

Anyone treating this as "describe an ad, get a video" will spend a lot of credits discovering the storyboard was wrong. The stills stage exists so you find that out for the price of an image.

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Going back

go_back_to returns to an earlier stage with the project intact. Changed your mind about the concept after seeing scene 3? Go back, update the brief, keep everything else.

Starting a fresh project loses the casting, the brief and the scenes you liked. Going back keeps them. Reach for it before you reach for a new chat.

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Where it fits

• Canvas chat: you know what you're selling but not what the ad looks like
• Templates: you want a known-good treatment and just need your product in it
• The generators: you know exactly what you want and want to specify it yourself

The chat is the most guided of the three, and the plan card makes it the least risky place to be uncertain.

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Try it

Open Canvas, attach a product photo, and say what you're advertising in one sentence. Stop at the plan card and read it. That costs nothing and it's the fastest way to see how the agent has understood you.

Then: what Canvas is · Canvas templates