Agent skill · creative production · steipete
nano-banana-pro
Nano Banana/Gemini image gen/edit: text/image input, 512-4K workflows.
Why this skill is useful
Adds executable scripts for image generation and editing using the Nano Banana API, which are not available in public documentation.
What it needs
Requires uv installed locally. Requires google account access. About 3k tokens when loaded. Last updated 2026-08-06. 6,510 stars on the source repository.
What this skill does
Nano Banana 2 Image Generation & Editing Generate new images or edit existing ones using Google's Nano Banana 2 API (Gemini 3.1 Flash Image). Usage Run the script using absolute path (do NOT cd to skill directory first): Generate new image: Edit existing image: Important: Always run from the user's current working directory so images are saved where the user is working, not in the skill directory. Default Workflow (draft → iterate → final) Goal: fast iteration without burning time on 4K until the prompt is correct. Draft (1K): quick feedback loop uv run ~/.codex/skills/nano-banana-pro/scripts/generateimage.py --prompt "<draft prompt>" --filename "yyyy-mm-dd-hh-mm-ss-draft.png" --resolution 1K Iterate: adjust prompt in small diffs; keep filename new per run If editing: keep the same --input-image for every iteration until you’re happy. Final (4K): only when prompt is locked uv run ~/.codex/skills/nano-banana-pro/scripts/generateimage.py --prompt "<final prompt>" --filename "yyyy-mm-dd-hh-mm-ss-final.png" --resolution 4K Resolution Options The Gemini 3.1 Flash Image API supports these output size values: 512 - compact ~512px-class resolution 1K (default) - ~1024px resolution 2K - ~2048px resolution 4K - ~4096px resolution Map user requests to API parameters: "512", "512px", "0.5K", "thumbnail", "tiny" → 512 No mention of resolution → 1K "low resolution", "1080", "1080p", "1K" → 1K "2K", "2048", "normal", "medium resolution" → 2K "high resolution", "high-res", "hi-res", "4K", "ultra" → 4K API Key The script checks for API key in this order: 1. --api-key argument (use if user provided key in chat) 2. GEMINIAPIKEY environment variable If neither is available, the script exits with an error message. Preflight + Common Failures (fast fixes) Preflight: command -v uv (must exist) test -n \"$GEMINIAPIKEY\" (or pass --api-key) If editing: test -f \"path/to/input.png\" Common failures: Error: No API key provided. …
How to use it
Reference it in AdaL, Claude Code, Cursor or any coding agent — nothing to install:
@skills steipete/nano-banana-pro