nano-banana-pro-openrouter

# Nano Banana Pro Image Generation Generate new images using OpenRouter's Nano Banana Pro (Gemini 3 Pro Image Preview). ## Usage Run the script using an absolute path (do NOT cd to the skill directory first): Generate new image: ```bash sh ~/.openclaw/workspace/skills/nano-banana-pro-openrouter/scripts/generate_image.sh --prompt "your image description" [--filename "output-name.png" | --filename auto] [--resolution 1K|2K|4K] [--api-key KEY] ``` Note: the shell version currently supports generation only (no input image editing). Important: - Images are always saved under `~/.openclaw/workspace/outputs/nano-banana-pro-openrouter` - If `--filename` contains a path, only the basename is used ## Default Workflow (draft -> iterate -> final) Goal: fast iteration without burning time on 4K until the prompt is correct. - Draft (1K): quick feedback loop - `sh ~/.openclaw/workspace/skills/nano-banana-pro-openrouter/scripts/generate_image.sh --prompt "<draft prompt>" --filename auto --resolution 1K` - Iterate: adjust prompt in small diffs; keep filename new per run - Final (4K): only when prompt is locked - `sh ~/.openclaw/workspace/skills/nano-banana-pro-openrouter/scripts/generate_image.sh --prompt "<final prompt>" --filename auto --resolution 4K` ## Resolution Options The Gemini 3 Pro Image API supports three resolutions (uppercase K required): - 1K (default) - ~1024px resolution - 2K - ~2048px resolution - 4K - ~4096px resolution Map user requests to API parameters: - 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 and Base URL The script checks for the API key in this order: 1. --api-key argument (use if user provided a key in chat) 2. OPENROUTER_API_KEY environment variable The API base URL must be set via OPENROUTER_BASE_URL. Use the full chat completions endpoint (for OpenRouter: `https://openrouter.ai/api/v1/chat/completions`). The script also loads .env files automatically (if present): - Current working directory .env - Skill directory .env Important: If a .env file exists, do not ask the user for the key up front. Just run the script and only ask if it errors with "No API key provided." ### OpenClaw Chat Execution Rules - OpenClaw does NOT auto-source the skill .env file - If `~/.openclaw/workspace/skills/nano-banana-pro-openrouter/.env` exists: 1. Use the `read` tool to read `.env` 2. Extract `OPENROUTER_API_KEY` and `OPENROUTER_BASE_URL` 3. Always pass the key via `--api-key` when running the script - Only ask the user if .env is missing or the key cannot be read - If the user asks for a timestamped filename, prefer `--filename auto` (do not handwrite dates) If neither is available, the script exits with an error message. ## Preflight and Common Failures (fast fixes) Preflight: - `command -v sh` (must exist) - `command -v curl` (must exist) - `command -v base64` (must exist) Common failures: - `Error: No API key provided.` -> read .env and retry with --api-key; if still failing, ask the user to set OPENROUTER_API_KEY - `Error: No API base URL provided.` -> ensure OPENROUTER_BASE_URL is set to a full chat completions endpoint - `Error loading input image:` -> wrong path or unreadable file; verify --input-image points to a real image - "quota/permission/403" style API errors -> wrong key, no access, or quota exceeded; try a different key/account ## Filename Generation Generate filenames with the pattern: `yyyy-mm-dd-hh-mm-ss-name.png` Format: `{timestamp}-{descriptive-name}.png` - Timestamp: Current date/time in format `yyyy-mm-dd-hh-mm-ss` (24-hour format) - Name: Descriptive lowercase text with hyphens - Keep the descriptive part concise (1-5 words typically) - Use context from the user's prompt or conversation - If unclear, use `image` Examples: - Prompt "A serene Japanese garden" -> `2025-11-23-14-23-05-japanese-garden.png` - Prompt "sunset over mountains" -> `2025-11-23-15-30-12-sunset-mountains.png` - Prompt "create an image of a robot" -> `2025-11-23-16-45-33-robot.png` - Unclear context -> `2025-11-23-17-12-48-image.png` Tip: To avoid incorrect timestamps, pass `--filename auto` and let the script generate the filename using the system clock. ## Image Editing (Not Supported in Shell Version) The shell script only supports generating new images. Editing an input image is not available in this version. ## Prompt Handling For generation: pass the user's image description as-is to --prompt. Only rework if clearly insufficient. ## Prompt Templates (high hit-rate) Use templates when the user is vague or when edits must be precise. Generation template: - "Create an image of: <subject>. Style: <style>. Composition: <camera/shot>. Lighting: <lighting>. Background: <background>. Color palette: <palette>. Avoid: <list>." ## Output - Saves PNG to `~/.openclaw/workspace/outputs/nano-banana-pro-openrouter` - If `--filename` includes a path, only the basename is used - Script outputs the full path to the generated image - Script also outputs `MEDIA_URL=file:///absolute/path` for each image ### Show the image in the reply - Use the MEDIA_URL value to attach the image in the model response - In OpenClaw, prefer sending a message with mediaUrl set to that file:// URL - Also include the file path in text for reference ## Examples Generate new image: ```bash sh ~/.openclaw/workspace/skills/nano-banana-pro-openrouter/scripts/generate_image.sh --prompt "A serene Japanese garden with cherry blossoms" --filename auto --resolution 4K ```