# Nano Banana Pro (image)

> Nano Banana Pro makes photoreal still images from text and from references. It is the best roasOS image model for identity, product placement and rendered typography.

Status: roasOS API v1.1. Catalog `model-catalog@2026-10-06.v5`, pricing `customer-pricing@2026-11-05.v15`. The endpoint `POST /v1/image/nano-banana-pro` is live. `POST /v1/generations` stays for one minor version as a deprecated alias (see "Today").

## Endpoint
POST https://api.roasos.com/v1/image/nano-banana-pro
Auth: Authorization: Bearer roasos_sk_… (scope api:write). Idempotency-Key required. quote_only / quote_id / webhook_url as in https://docs.roasos.com/llms.txt.

## Good at
Nano Banana Pro is Google's state-of-the-art image generation and editing model (fal tags: realism, typography). Use it for the final hero image, for a person who must look the same across images, and for a product that must keep its exact label and shape. It holds up to 14 reference images and it follows a long scene description with camera, light and material named. It renders 4K when fine detail matters. It is the only image model that the scene and avatar endpoints use. It does not do masked inpaint; use /v1/image-edit/gpt-image-2.5 for that.

## Pricing
Unit: image. Pricing key: `nano-banana-pro`.

| request | credits |
|---|---|
| `1_image_2K` | 2 |
| `1_image_1K` | 2 |
| `1_image_4K` | 4 |
| `4_images_4K` | 15 |

Credits come from the roasOS pricing table (`MODEL_COSTS`) through the catalog. No other field changes the price.

## Modes
- `text-to-image`
- `edit`

The worker derives the mode from the media fields of the request.
Provider endpoints: `fal-ai/nano-banana-pro` · `fal-ai/nano-banana-pro/edit`.

## Request fields
| field | type | required | default | rule |
|---|---|---|---|---|
| `ad_look` | enum | no | — | `designed`, `native`, `ui` |
| `ad_set` | object | no | — | `{ id, index, total }` |
| `alter` | object | no | — | `{ mode, who, new_person, clothes, outfit, object, product, keep, multi_shot }` |
| `aspect_ratio` | enum | no | `1:1` | `auto`, `21:9`, `16:9`, `3:2`, `4:3`, `5:4`, `1:1`, `4:5`, `3:4`, `2:3`, `9:16` |
| `avatar_id` | string | no | — | UUID |
| `avatar_outfit` | string | no | — | ≤ 500 characters |
| `num_images` | integer | no | `1` | 1–4 |
| `product_id` | string | no | — | UUID |
| `product_images` | string[] | no | — | ≤ 14 items; only in `edit` |
| `prompt` | string | no | — | ≥ 1 character; ≤ 8,000 characters |
| `prompt_mode` | enum | no | — | `wrapped`, `exact` |
| `quote_id` | string | no | — | UUID |
| `quote_only` | boolean | no | `false` | — |
| `references` | string[] | no | — | ≤ 14 items; only in `edit` |
| `resolution` | enum | no | `2K` | `1K`, `2K`, `4K` |
| `seed` | integer | no | — | -2147483648–2147483647 |
| `source_image` | string | no | — | https URL; ≤ 4,096 characters |
| `wait_timeout_seconds` | integer | no | `0` | 0–60 |
| `webhook_url` | string | no | — | https URL; ≤ 4,096 characters |

The schema is strict: a field that is not in this table returns `400 unsupported_option`. Field names are the roasOS role names, one name per role across every family.

## Media
- `avatar_id` — identity; the saved character reference sheet, with a derived portrait only where the model requires a single face or source frame
- `product_id` — product; resolves to the product image list
- `product_images` — product reference images
- `references` — style and appearance references

| role | items | max size | content types | duration |
|---|---|---|---|---|
| `product_images` | ≤ 14 | 10 MB | `image/jpeg`, `image/png`, `image/webp` | — |
| `references` | ≤ 14 | 10 MB | `image/jpeg`, `image/png`, `image/webp` | — |

- Refused: `elements`, `reference_images`, `image_url`, `end_image_url`, `scene_id`, `scene_image`, `video_urls`, `video_url`, `audio_urls`, `audio_url`, `voice_id`. A refused role returns `400 unsupported_option`.
- Every URL must be an immutable object on `https://cdn.roasos.com/…` that your workspace owns; any other URL is `400 reference_media_not_workspace_owned`. Upload with `POST /v1/uploads` (direct POST of the bytes to `put_url`, or a `source_url` import), then use the returned CDN URL.

## Prompt
Limit: 8,000 characters for the caller. The worker wrapper counts toward the 10,000-character engine cap. No tag syntax; the worker orders the references and names the roles.
- Write one scene: subject, action, setting, light, camera, material.
- Put identity and product rules in the media roles, not in the prompt text. The wrapper tells the model which image is the person, which is the product, and which is style only.
- Say what the person does and where the product is; do not describe the person's face.
- Give the exact text to render inside quotation marks.
- State the framing (close-up, half body, full body) and the aspect ratio in words when it matters.
- On a bad result, write a new prompt that names the fix; do not resend the same payload.

## Not exposed
- `output_format`: pinned to `png`.
- `safety_tolerance`: pinned to `4`.
- `enable_web_search`: pinned to `false`.
- `limit_generations`: pinned to `true`.
- `system_prompt`: not accepted by this public endpoint.
- `sync_mode`: not accepted by this public endpoint.

## Result
Result kind `image`. Always present: nothing. Present when the run produces it: `avatar_id`, `full_body_url`, `images`, `portrait_url`, `provider_seed`, `reference_sheet`, `url`.
```json
{ "data": { "id": "gen_…", "kind": "image", "model": "nano-banana-pro", "status": "completed", "result": {"avatar_id":"00000000-0000-4000-8000-000000000000","full_body_url":"https://cdn.roasos.com/workspaces/ws_01/full_body_url","images":["https://cdn.roasos.com/workspaces/ws_01/images-1.png"],"portrait_url":"https://cdn.roasos.com/workspaces/ws_01/portrait_url","provider_seed":0,"reference_sheet":"https://cdn.roasos.com/workspaces/ws_01/reference_sheet","url":"https://cdn.roasos.com/workspaces/ws_01/result"} } }
```
Files live on `https://cdn.roasos.com` and are immutable; a result URL can be a media input to the next call. Poll `GET /v1/jobs/{id}/status` → `{ id, status, updated_at }`, then `GET /v1/jobs/{id}/result` (`409 run_not_completed` until the job is `completed`, `failed` or `canceled`). Statuses: `queued → processing → completed | failed | canceled`.

## Example
```bash
# 1. quote — nothing is spent
curl -X POST https://api.roasos.com/v1/image/nano-banana-pro \
  -H "Authorization: Bearer roasos_sk_live_…" \
  -H "Idempotency-Key: 0f1c9e2a-nano-banana-pro-0001" \
  -H "Content-Type: application/json" \
  -d '{"quote_only":true,"prompt":"A woman holds the bottle at eye level in a bright kitchen, morning light, static camera."}'
# → 200 { "data": { "kind": "quote", "quote_id": "q_7Hk…", "credits": 2, "expires_at": "…", "confirmation": { "model": "nano-banana-pro", "example": "1_image_2K" } } }

# 2. run — the same body and the same Idempotency-Key, quote_id instead of quote_only
curl -X POST https://api.roasos.com/v1/image/nano-banana-pro \
  -H "Authorization: Bearer roasos_sk_live_…" \
  -H "Idempotency-Key: 0f1c9e2a-nano-banana-pro-0001" \
  -H "Content-Type: application/json" \
  -d '{"quote_id":"q_7Hk…","prompt":"A woman holds the bottle at eye level in a bright kitchen, morning light, static camera."}'
# → 201 { "data": { "id": "gen_…", "kind": "image", "model": "nano-banana-pro", "status": "queued", "credits_reserved": 2, "links": { "status": "/v1/jobs/gen_…/status", "result": "/v1/jobs/gen_…/result" } } }

# 3. poll
curl https://api.roasos.com/v1/jobs/gen_…/status -H "Authorization: Bearer roasos_sk_live_…"
curl https://api.roasos.com/v1/jobs/gen_…/result -H "Authorization: Bearer roasos_sk_live_…"
```

## Today
POST /v1/generations `{ "type": "image", "model": "nano-banana-pro", "prompt": "…", "options": { "aspect_ratio", "resolution", "num_outputs", "reference_images" (≤ 9), "seed" } }`. Today's public API has no `avatar_id`, `product_images` or `product_id` role, and it sends the prompt raw (no placement wrapper). `aspect_ratio` on today's path is `1:1, 16:9, 9:16, 4:3, 3:4, 21:9` (no `auto`, `4:5`, `5:4`, `3:2`, `2:3`).

## See also
https://docs.roasos.com/models/image/nano-banana-pro · https://api.roasos.com/v1/catalog/image/nano-banana-pro · fal-ai/nano-banana-pro · fal-ai/nano-banana-pro/edit