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Image generation steps turn a text prompt into an image you can display in chat, pass to another step, or hand back as a downloadable link. Airia offers more than one image-generation step — pick the tab for the step you’re using.
💡 Displaying the result is the same idea for every step: an image step returns data (a URL or encoded bytes), not a rendered picture. To show it in the conversation, render it as markdown with a Message Formatter step placed downstream — each tab below shows the exact reference.
Nano Banana and Nano Banana Pro are image-generation steps powered by Google’s Gemini image models.
  • Nano Banana — Gemini 2.5 Flash Image. Fast generation at 1024px, with customizable aspect ratios.
  • Nano Banana Pro — Gemini 3 Pro Image. Professional quality with resolutions up to 4K (1K / 2K / 4K).
💡 Find them in Steps → Actions → Image Models → Gemini.

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Configuration

💡 Choosing an Output Format: Use Download URL when you want to display or share the image (it gives you a plain link you can embed or hand to a user). Use Base64 when a downstream step needs the raw bytes inline.

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Output

Each step returns a GeminiGenerateImageResponse:
  • Images[] — One entry per generated image. Each has:
    • ImageUrl — the signed download URL (when Output Format = Download URL).
    • ImageDataBase64 — the base64-encoded bytes (when Output Format = Base64).
    • MimeType — e.g. image/png.
  • Message — any text the model returned alongside the image.
  • TotalCount — number of images generated.

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Displaying the image in chat

Wire a Message Formatter step after Nano Banana:
  1. On the Nano Banana step, set Output Format → Download URL (and, if you want the link to stay valid, set URL Expiry → Perpetual).
  2. In the Message Formatter, use markdown’s image syntax pointing at the step’s ImageUrl:
    • Inputs.Nano_Banana refers to the upstream step by its title, with spaces replaced by underscores (Nano Banana → Nano_Banana, Nano Banana 1 → Nano_Banana_1). See Variables for the naming rules.
    • .Output.Images[-1] grabs the most recently generated image ([-1] is the last item); use [0] for the first.
    • ![alt](url) is markdown’s image tag, so the chat surface renders the picture inline.
Add a download link. Because Download URL gives a real, shareable link, reuse the same ImageUrl in a markdown link (drop the leading !) to offer a click-to-download option:
💡 Using Base64 output instead? Embed it as a data URI rather than a plain URL:

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Troubleshooting

The image won’t display / the link is empty
  • The Message Formatter references ImageUrl, but the step is set to Base64. Switch Output Format → Download URL, or embed the base64 data URI instead (see above).
The variable doesn’t resolve
  • Check the step title in the token. The default step Nano Banana is referenced as Inputs.Nano_Banana; spaces become underscores, and a numbered duplicate like Nano Banana 1 becomes Nano_Banana_1. The token must match the title exactly.
The download link stops working after a while
  • The signed URL expired. Increase URL Expiry, or set it to Perpetual for a non-expiring link.
Authentication errors
  • Either select a valid Google API Key credential on the step, or leave the credential blank to fall back to the Airia Key.