Nano Banana Skill

Generate, edit, and iterate on visual imagery conversationally using Google's native Nano Banana image generation foundation models (gemini-nano-banana-2.1, gemini-3.1-flash-lite-image, gemini-3.1-flash-image, gemini-3-pro-image) via the official gemini-api CLI (gemini-api image) for terminal and coding agent workflows, or the Google Gen AI SDKs for application backends.

Prerequisites: gemini-api CLI Setup

The gemini-api CLI is a zero-dependency binary that writes generated images directly to disk and prints only the output file path to stdout, keeping raw base64 payloads out of agent context windows.

# 1. Verify or install gemini-api CLI on macOS and Linux
command -v gemini-api >/dev/null 2>&1 || (curl -fsSL https://raw.githubusercontent.com/google-gemini/gemini-api-cli/main/scripts/install.sh | bash)
# Windows (PowerShell): iwr -useb https://raw.githubusercontent.com/google-gemini/gemini-api-cli/main/scripts/install.ps1 | iex

# 2a. Authenticate with a Gemini API Key (environment variable or OS keychain)
export GEMINI_API_KEY="your-api-key"
# Or store credentials in the OS keychain:
gemini-api configure --api-key "your-api-key"