What is gemini-nano-banana-2?

An image-generation and image-editing tool using Google's Gemini Nano Banana 2 model.

Generating new images, editing images, choosing output sizes and shapes, and controlling the model's reasoning and search options.

It helps create or change images from written instructions or an existing image file.

gemini-nano-banana-2 — Skill for Claude Code and Codex by tamtom

Install

Getting it into your agent

One page per mod, every tool's command on it. A separate URL per tool would split the same page into five that compete with each other.

Any agent

npx skills add tamtom/image-generation-skills --skill gemini-nano-banana-2

Clone the repo

git clone --depth 1 https://github.com/tamtom/image-generation-skills

Made for: Claude Code, Codex.

Wrote this? Show the measurements

A badge with what this costs and how it scanned, read live from this page, so it follows the numbers instead of freezing them. Markdown for a README, HTML for a documentation site or a project page.

README.md

[![agentmods](https://agentmods.dev/badge/skills/tamtom/image-generation-skills/gemini-nano-banana-2/github.svg)](https://agentmods.dev/skills/tamtom/image-generation-skills/gemini-nano-banana-2)

Your own site

<a href="https://agentmods.dev/skills/tamtom/image-generation-skills/gemini-nano-banana-2"><img src="https://agentmods.dev/badge/skills/tamtom/image-generation-skills/gemini-nano-banana-2/github.svg" alt="Measured on agentmods" height="20"></a>

Or the 80×15 button, for a site that already has a row of RSS and ATOM ones. Only the verdict fits; the numbers stay here.

Your own site · 80×15

<a href="https://agentmods.dev/skills/tamtom/image-generation-skills/gemini-nano-banana-2"><img src="https://agentmods.dev/badge/skills/tamtom/image-generation-skills/gemini-nano-banana-2.svg" alt="Reviewed on agentmods" width="80" height="20"></a>

Per session 153 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.

When invoked 4,225 The whole file, excluding the scripts and references it only reads on demand.

Security scan A 0 findings. A grade says what 26 rules found in the file — not that it is safe.

Origin original No closer match found in the catalogue.

Token cost

What it costs to keep this loaded

Counted locally with the o200k_base tokenizer, which is exact for GPT models; Claude uses its own tokenizer and its counts differ. Treat this as one consistent yardstick across the catalogue rather than a bill. Prices are per million input tokens.

Model	Per session	Once invoked
Fable 5.1	$0.00153	$0.04225
Opus 5.5	$0.00061	$0.01690
Sonnet 5.5	$0.00031	$0.00845
Haiku 4.5	$0.00015	$0.00422

Measured 2mo ago against content hash 67ab4cd71ed0, method: parsed. Prices are Anthropic first-party input rates as of 2026-10-07, from the pricing page.

Security

Grade A, and why

gemini-nano-banana-2 scanned grade A with 0 findings against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured 2mo ago.

The scan reads SKILL.md. This mod also ships 1 executable file (scripts/generate_image.py), listed below but not scanned — reading those needs a real analyzer, not pattern matching.

A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.

Nothing flagged

None of the 26 patterns this scan looks for appear in this file: no shell pipes, no recursive deletes, no credential paths, no hidden text, no instruction-override or anti-refusal phrasing, no agent-config snooping. That is not a guarantee, it is the absence of the things that are checkable.

skills/gemini-nano-banana-2/SKILL.md · 290 lines

How it starts

The opening of the file, as written. The whole thing — 290 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Gemini Nano Banana 2 - Image Generation & Editing

Generate new images or edit existing ones using Google's Gemini Nano Banana 2 model (gemini-3.1-flash-image-preview) via the Gemini API. This is the latest and most capable Gemini image model, featuring advanced reasoning ("Thinking") with controllable levels, high-fidelity text rendering, Google Web + Image Search grounding, output from 512 up to 4K resolution, and 14 aspect ratios.

Usage

Run the script using absolute path (do NOT cd to skill directory first):

Generate new image:

uv run ~/.claude/skills/gemini-nano-banana-2/scripts/generate_image.py --prompt "your image description" --filename "output.png" [--aspect-ratio 1:1|1:4|1:8|2:3|3:2|3:4|4:1|4:3|4:5|5:4|8:1|9:16|16:9|21:9] [--resolution 512|1K|2K|4K] [--output-format png|webp|jpeg] [--response-modality text-and-image|image-only] [--thinking-level minimal|high] [--google-search] [--image-search] [--yes] [--cost-threshold 0.10] [--api-key KEY]

Edit existing image:

uv run ~/.claude/skills/gemini-nano-banana-2/scripts/generate_image.py --prompt "editing instructions" --filename "output.png" --input-image "path/to/input.png" [--aspect-ratio 1:1] [--resolution 2K] [--api-key KEY]

Edit with multiple reference images (compositing/style transfer, up to 14 images):

uv run ~/.claude/skills/gemini-nano-banana-2/scripts/generate_image.py --prompt "combine the subject from first image with the style of second image" --filename "output.png" --input-image "subject.png" --input-image "style-ref.png" [--resolution 2K] [--api-key KEY]

Generate with Google Web Search grounding (real-time data):

uv run ~/.claude/skills/gemini-nano-banana-2/scripts/generate_image.py --prompt "visualize the current weather forecast for San Francisco" --filename "output.png" --google-search --aspect-ratio 16:9 [--api-key KEY]

Generate with Google Image Search grounding (visual reference from the web):

uv run ~/.claude/skills/gemini-nano-banana-2/scripts/generate_image.py --prompt "a detailed painting of a resplendent quetzal bird resting on a flower" --filename "output.png" --image-search [--api-key KEY]

Read the full file on GitHub · 290 lines

Files

What ships with it

1 file beside SKILL.md in the same directory: the scripts, references and assets a skill reads on demand. Not counted in the per-session cost; read them before you install if any of them is executable.

scripts/generate_image.py 14 KB runs code

Changes

What this file has done since we first saw it

Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.

2mo ago First seen · 290 lines · 153 tokens per session scan A 67ab4cd71ed0

Subscribe to this mod's changes

gemini-nano-banana-2 is a skill published in the GitHub repository tamtom/image-generation-skills (9 stars, last pushed 7mo ago), licensed MIT. It adds 153 tokens to every session and 4,225 once invoked, about $0.0006 per session on Opus 5.5. A static security scan graded it A with 0 findings. No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-31.

Creative and media

gemini-nano-banana-2 next to 6 skills from other repositories
Mod	Type	Stars	Last push	Licence	Scan	Tokens	Works with
gemini-nano-banana-2tamtom/image-generation-skills	Skill	9	7mo ago	MIT	A	153	Claude Code, Codex
imagegenopenai/codex	Skill	134k	today	Apache-2.0	A	113	Codex
playwright-climicrosoft/playwright	Skill	99k	today	Apache-2.0	A	19	Claude Code
local-ai-agentsmicrosoft/ai-agents-for-beginners	Skill	79k	today	MIT	A	200	Claude Code, Codex
systematic-debuggingobra/superpowers	Skill	314k	3d ago	MIT	A	21	Claude Code
next-cache-components-adoptionvercel/next.js	Skill	143k	today	MIT	A	95	Claude Code
next-partial-prefetching-adoptionvercel/next.js	Skill	143k	today	MIT	A	103	Claude Code