Nano Banana 2 — Pro Pack on RunComfy
Google Nano Banana 2 — the flash-tier text-to-image model in the Gemini family — hosted on the RunComfy Model API. Optimized for ideation, social-thumbnail batches, and rapid drafts with strong in-image typography.
bash
npx skills add agentspace-so/runcomfy-skills --skill nano-banana-2 -g
When to pick this model (vs siblings)
Nano Banana 2 is the flash-tier of the Google image-gen line. Pick it when iteration speed and predictable framing matter more than maximum detail.
| You want | Use |
|---|
| Rapid drafts, social thumbnails, batch variants | Nano Banana 2 |
| In-image typography with predictable rendering | Nano Banana 2 |
| Web-grounded image (current events / real entities) | Nano Banana 2 + |
| Image edit (preserve subject, swap background) | Nano Banana Edit (sibling skill) |
| Heavy stylization, painterly look | Flux 2 |
| Maximum prompt adherence + multilingual text | GPT Image 2 |
| 2K–4K hero shots, max realism | Seedream 5 |
| Hyperrealistic portrait | Nano Banana Pro |
If the user said "Nano Banana" / "nano-banana-2" / "Gemini image" explicitly, route here regardless. If they said "Nano Banana" without specifying 2 vs Pro, default to Pro for portraits and 2 for everything else.
Prerequisites
- RunComfy CLI —
- RunComfy account — opens a browser device-code flow.
- CI / containers — set instead of .
Endpoints + input schema
google/nano-banana-2/text-to-image
| Field | Type | Required | Default | Notes |
|---|
| string | yes | — | Subject-first description. |
| int | no | 1 | 1–4. Use 4 for ideation rounds. |
| int | no | 0 | Reuse for reproducibility. |
| enum | no | | , , , , , , , , , , . |
| enum | no | | (drafts), (default), (final), (max). |
| enum | no | | , , . |
| int | no | 4 | 1 (strict) – 6 (permissive). |
| bool | no | true | Limit each prompt round to one generation. |
| bool | no | false | Adds web grounding (extra cost + latency). |
For image edit (preserve subject + apply changes), see the sibling
skill.
How to invoke
Default draft (1K, square, png):
bash
runcomfy run google/nano-banana-2/text-to-image \
--input '{"prompt": "<user prompt>"}' \
--output-dir <absolute/path>
Vertical 4-up batch for ideation:
bash
runcomfy run google/nano-banana-2/text-to-image \
--input '{
"prompt": "<user prompt>",
"num_images": 4,
"aspect_ratio": "9:16",
"resolution": "0.5K"
}' \
--output-dir <absolute/path>
Final at 2K with seed lock:
bash
runcomfy run google/nano-banana-2/text-to-image \
--input '{
"prompt": "<user prompt>",
"resolution": "2K",
"aspect_ratio": "16:9",
"seed": 42
}' \
--output-dir <absolute/path>
Web-grounded (current event / real entity):
bash
runcomfy run google/nano-banana-2/text-to-image \
--input '{
"prompt": "<prompt referencing a real-world event from this week>",
"enable_web_search": true
}' \
--output-dir <absolute/path>
Prompting — what actually works
Subject-first declarative grammar. "A cinematic close-up portrait of an American woman standing under neon lights in rainy Tokyo, shallow depth of field, reflective wet streets, ultra-detailed, realistic skin texture" — primary subject, then action, environment, style, camera. Front-load subject; trail with directives.
Exact text quoting for in-image typography. "The label reads 'AURA' in clean bold sans-serif, centered, white on black" — quote the literal characters. Specify placement and font style. Don't say "with the brand name on it" and hope.
Consistent seeds for refinement. Lock
when iterating a single prompt across small variants — keeps composition stable.
Web-grounding, sparingly. Turn on
only when the prompt names current events / real entities. Adds latency + cost; off by default.
Don't conflict styles. "minimalist + ornate + retro + cyberpunk" cancels. Pick 1–2 anchors.
Anti-patterns:
- Trying to verbally describe a stable subject identity — use the edit endpoint with image refs instead.
- Asking for resolutions outside the 4 tiers → 422.
- Aspect ratios outside the 11 supported values → 422.
- Non-quoted in-image text → unpredictable rendering.
Where it shines
| Use case | Why Nano Banana 2 |
|---|
| Marketing draft thumbnails (batch of 4) | Fast iteration at 0.5K, then promote winner to 2K |
| Social-platform-native | Wide aspect ratio support including 9:16, 4:5, 21:9 |
| In-image typography for posters / cards | Predictable text rendering when characters are quoted |
| Web-grounded current-event imagery | integrates fresh info |
| Reproducible variant testing | Strong seed + consistent framing |
Sample prompts (verified to produce strong results)
Cinematic portrait (page example):
A cinematic close-up portrait of an American woman standing under neon
lights in rainy Tokyo, shallow depth of field, reflective wet streets,
ultra-detailed, realistic skin texture
Brand-asset card with quoted text:
A minimalist 16:9 product card: a matte black ceramic mug centered on a
soft warm-grey paper background, rim highlight from upper-left, the
headline "Brewed Quietly" in clean bold sans-serif top-right, balanced
negative space below, e-commerce ready, clean studio lighting
Vertical platform-native:
A 9:16 vertical hero for a wellness brand: a single ceramic teacup on a
linen runner, soft morning side-light, the words "Slow Down" in
hand-drawn serif large at the top, gentle steam rising, neutral color
palette, uncluttered
Limitations
- Still images only. No video on this endpoint.
- Max 4 outputs per request.
- Web search adds latency + cost — only enable on demand.
- 2K / 4K cost more — default to 1K unless user asked for higher.
- For image edit, use the endpoint — not this one.
Exit codes
| code | meaning |
|---|
| 0 | success |
| 64 | bad CLI args |
| 65 | bad input JSON / schema mismatch |
| 69 | upstream 5xx |
| 75 | retryable: timeout / 429 |
| 77 | not signed in or token rejected |
How it works
The skill invokes
runcomfy run google/nano-banana-2/text-to-image
with a JSON body matching the schema. The CLI POSTs to
https://model-api.runcomfy.net/v1/models/google/nano-banana-2/text-to-image
, polls the request, fetches the result, and downloads any
/
URL into
.
cancels the remote request before exit.
Security & Privacy
- Token storage: writes the API token to
~/.config/runcomfy/token.json
- Input boundary: the user prompt is passed as a JSON string to the CLI via . The CLI does NOT shell-expand the prompt; it transmits the JSON body directly to the Model API over HTTPS. No shell injection surface from prompt content.
- Third-party content: image / mask / video URLs you pass are fetched by the RunComfy model server, not by the CLI on your machine. Treat external URLs as untrusted; image-based prompt injection is a known risk for any image-edit / video-edit model.
- Outbound endpoints: only (request submission) and / (download whitelist for generated outputs). No telemetry, no callbacks.
- Generated-file size cap: the CLI aborts any single download > 2 GiB to prevent disk-fill from a malicious or runaway model output.