A Python tool for creating and editing images with Google's Gemini-based Nano Banana models.

Use it for text-to-image work, editing existing images, using local reference images repeatedly, generating batches, inspecting requests, and saving raw responses for debugging.

It puts single requests, repeated variations, option checks, and custom Gemini-compatible endpoints behind one consistent command. A dry-run can reveal request problems before an image is generated.

nanobanana — Skill for Codex by GargantuaX/openskills

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 GargantuaX/openskills --skill nanobanana

Clone the repo

git clone --depth 1 https://github.com/GargantuaX/openskills

Made for: 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/gargantuax/openskills/nanobanana/github.svg)](https://agentmods.dev/skills/gargantuax/openskills/nanobanana)

Your own site

<a href="https://agentmods.dev/skills/gargantuax/openskills/nanobanana"><img src="https://agentmods.dev/badge/skills/gargantuax/openskills/nanobanana/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/gargantuax/openskills/nanobanana"><img src="https://agentmods.dev/badge/skills/gargantuax/openskills/nanobanana.svg" alt="Reviewed on agentmods" width="80" height="20"></a>

Per session 67 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.

When invoked 1,035 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. Third-party audits

Socket warn 15 Sept 2026
Snyk pass 15 Sept 2026

How audits are shown

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	$0.00067	$0.01035
Opus 5.5	$0.00027	$0.00414
Sonnet 5.5	$0.00013	$0.00207
Haiku 4.5	$0.00007	$0.00103

Measured 2mo ago against content hash 6be368485449, method: parsed. Prices are Anthropic first-party input rates as of 2026-10-07, from the pricing page.

Security

Grade A, and why

nanobanana 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 2 executable files (scripts/nanobanana.py, tests/test_nanobanana.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/nanobanana/SKILL.md · 95 lines

How it starts

The opening of the file, as written. The whole thing — 95 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Nano Banana

A single Python entrypoint for Gemini-native Nano Banana image generation and editing, with model aliases, strict option validation, batch runs, and custom endpoint support.

Workflow

Open references/config.md to choose environment variables and override order.
Open references/models-and-api.md to pick the right Nano Banana tier and check model-specific constraints.
Prefer gemini-3.1-flash-image-preview (nanobanana-2) unless you need either the fastest low-cost default (nanobanana) or the highest-fidelity reasoning model (nanobanana-pro).
Run scripts/nanobanana.py generate for one request or scripts/nanobanana.py batch for repeated variants.
Add --dry-run first when the main risk is the payload shape, endpoint, or model-specific option support.
Pass --base-url or GEMINI_BASE_URL when you need a custom Gemini-compatible gateway.
Add --save-response <path> on generate when you need the raw JSON body for debugging.

Commands

Single text-to-image request:

python .\skills\nanobanana\scripts\nanobanana.py generate `
  --prompt "A retro-futurist product hero illustration for a developer tool" `
  --output .\out\hero.png `
  --model nanobanana-2 `
  --ratio 16:9 `
  --size 2K

Edit an existing image with two local references:

python .\skills\nanobanana\scripts\nanobanana.py generate `
  --prompt "Turn these references into a clean launch poster with legible title text" `
  --input-image .\refs\subject.png `
  --input-image .\refs\background.png `
  --output .\out\poster.png `
  --model nanobanana-pro `
  --ratio 4:5 `
  --size 2K

Use a custom Gemini-compatible gateway:

python .\skills\nanobanana\scripts\nanobanana.py generate `
  --prompt "A bold mascot sticker pack" `
  --output .\out\stickers.png `
  --base-url http://your-gateway.example.com/v1beta `
  --auth-mode bearer

Batch-generate five variants:

Read the full file on GitHub · 95 lines

Files

What ships with it

6 files 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.

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 · 95 lines · 67 tokens per session scan A 6be368485449

Subscribe to this mod's changes

nanobanana is a skill published in the GitHub repository GargantuaX/openskills (7 stars, last pushed 6mo ago), licensed MIT. It adds 67 tokens to every session and 1,035 once invoked, about $0.0003 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

nanobanana next to 6 skills from other repositories
Mod	Type	Stars	Last push	Licence	Scan	Tokens	Works with
nanobananaGargantuaX/openskills	Skill	7	6mo ago	MIT	A	67	Codex
imagegenopenai/codex	Skill	134k	today	Apache-2.0	A	113	Codex
local-ai-agentsmicrosoft/ai-agents-for-beginners	Skill	79k	yesterday	MIT	A	200	Claude Code, Codex
playwright-climicrosoft/playwright	Skill	100k	yesterday	Apache-2.0	A	19	Claude Code
browser-automationopenclaw/openclaw	Skill	394k	today	MIT	A	36	Claude Code
systematic-debuggingobra/superpowers	Skill	314k	4d ago	MIT	A	21	Claude Code
next-cache-components-adoptionvercel/next.js	Skill	143k	today	MIT	A	95	Claude Code