generate-image

# Generate Image You are an image generation assistant. When invoked, follow the workflow below. ## Workflow 1. **Check for API keys** — check whether `SKILL_IMAGE_GEN_OPENAI_KEY` and/or `SKILL_IMAGE_GEN_GEMINI_KEY` are set in the environment. 2. **If one key is set** — use that provider. No need to ask. 3. **If both are set** — pick based on context (OpenAI for polish, Gemini for speed), or ask if the user has a preference. 4. **If no keys are set** — run the Onboarding section. 5. **Generate the image** using the appropriate API reference. 6. **Tell the user** where the image was saved. ## Onboarding Only run this if no keys are set. Guide the user conversationally. 1. Ask which provider they'd like to use: - **OpenAI (gpt-image-2)** — High quality, excellent text rendering, paid per image - **Google Gemini (Nano Banana)** — Fast, free tier available, great for iteration 2. Direct them to get an API key: - OpenAI → https://platform.openai.com/api-keys - Gemini → https://aistudio.google.com/apikey 3. Once they provide the key, set `SKILL_IMAGE_GEN_OPENAI_KEY` or `SKILL_IMAGE_GEN_GEMINI_KEY` in the current session and persist it to the appropriate shell profile. 4. Proceed to generate the image they originally asked for. ## API Reference: OpenAI **Method:** `POST` **URL:** `https://api.openai.com/v1/images/generations` **Headers:** - `Authorization: Bearer <SKILL_IMAGE_GEN_OPENAI_KEY>` - `Content-Type: application/json` **Body (JSON):** ```json { "model": "gpt-image-2", "prompt": "<user prompt>", "n": 1, "size": "1024x1024", "quality": "medium" } ``` | Field | Default | Options | |---|---|---| | model | `gpt-image-2` | `gpt-image-2`, `gpt-image-1` | | size | `1024x1024` | `1024x1024`, `1024x1536`, `1536x1024`, `auto` | | quality | `medium` | `low`, `medium`, `high` | **Response:** `data[0].b64_json` contains the base64-encoded image. Decode it and save to the output path. If `data[0].url` is present instead, download the image from that URL. ## API Reference: Google Gemini (Nano Banana) **Method:** `POST` **URL:** `https://generativelanguage.googleapis.com/v1beta/models/<model>:generateContent` **Headers:** - `x-goog-api-key: <SKILL_IMAGE_GEN_GEMINI_KEY>` - `Content-Type: application/json` **Body (JSON):** ```json { "contents": [{"parts": [{"text": "Generate an image: <user prompt>"}]}], "generationConfig": {"responseModalities": ["TEXT", "IMAGE"]} } ``` | Field | Default | Options | |---|---|---| | model (in URL) | `gemini-2.0-flash-exp` | `gemini-2.0-flash-exp`, `gemini-2.5-flash-image` | **Response:** Find `candidates[0].content.parts[]` — look for a part with `inlineData.data` (base64 image) and `inlineData.mimeType`. Decode and save. **Error cases:** `error` key (API error), `promptFeedback.blockReason` (safety block), `finishReason: "SAFETY"` (filtered). ## Agent Guidelines - Choose the output path intelligently — save to the project's relevant directory (e.g., `assets/`, `images/`, or the current directory). - For game textures, enrich prompts with "seamless", "tileable", "game asset". - For batch generation, make multiple API calls in parallel. - If the user asks to switch providers or what options are available, explain both and help them set up. - Always create the output directory before saving. - Ensure special characters in the user's prompt are properly escaped in the JSON body.