Generate illustration images for articles and documentation with a Codex-first workflow, OpenAI API fallback, and Gemini fallback.

Image Generation Skill Generate illustration images for blog posts, documentation, and technical articles. The workflow is provider aware: 1. Codex built in path first — when the current agent is Codex and the built in image gen tool is available, use it directly. This path does not require OPENAI API KEY . 2. OpenAI API fallback — outside Codex, or when the built in tool is unavailable, use the local script with OPENAI API KEY if present. 3. Gemini fallback — if OpenAI API generation is unavailable or fails, use the same script with GEMINI API KEY and the existing Gemini image model. Load provider specific references only when needed: Codex built in path: references/codex built in.md OpenAI API fallback: references/openai api.md Gemini fallback: references/gemini api.md When to Use User asks to generate an illustration, diagram, concept image, article visual, or documentation visual User is writing an article and needs visual explanations for concepts or workflows User explicitly asks for a generated raster image Step 1: Determine the Image Requirements Before generating, clarify only what is necessary: 1. What to illustrate — the concept, architecture, flow, or scene 2. Language — default to English for both prompt and text in image. Only use another language if the user explicitly requests it 3. Save location — see "Output Path" below 4. Style/color preferences — if user has specific needs, use them; otherwise use the default style Step 2: Select the Provider Path Path A: Codex Built In Use this path when: The current agent is Codex The built in image gen tool is available The user did not explicitly request API/CLI execution Read references/codex built in.md , generate with the built in tool, then move/copy the final image into the workspace if it is project bound. Path B: Script Auto Fallback Use this path when: The current agent is not Codex The built in tool is unavailable The user explicitly asks for API/CLI execution Run: The script uses provider auto by default: 1. Try OpenAI API when OPENAI API KEY is set 2. If OpenAI API fails or is not configured, try Gemini when GEMINI API KEY is set 3. If neither credential is available, report the missing environment variables Step 3: Craft the Prompt Default Style Prefix The script automatically prepends this style prefix unless style prefix or no style is used: Use a clean, modern color palette with soft tones. Minimalist flat illustration style with clear visual hierarchy. Professional and polished look suitable for technical blog articles. No photorealistic rendering. No excessive gradients or shadows. For the Codex built in path, include the same style guidance directly in the prompt unless the user requested a different style. Prompt Writing Guidelines Be specific about visual elements, relationships, and layout For technical concepts: describe the components and how they connect For architecture diagrams: list the layers/components and data flow direction For flow diagrams: describe the steps and direction of flow If text labels are needed in the image, spell them out explicitly and keep text short Default language is English; use another language only when requested Example Prompts Architecture diagram: Concept illustration: Step 4: Parameters Default Parameters Parameter Default Notes Provider auto in script; Codex built in when available Codex built in first, then OpenAI API, then Gemini OpenAI model gpt image 2 Used by script fallback Gemini model gemini 3.1 flash image Used by script fallback Aspect ratio 16:9 Landscape, ideal for article illustrations Image size 1K Good balance of quality and cost Style Minimal, clean, soft tones Auto prepended by script Language English Prompt and in image text Script Options When to Change Defaults Scenario Change Higher quality final asset image size 2K or openai quality high Portrait/vertical image aspect ratio 3:4 or aspect ratio 9:16 Square image aspect ratio 1:1 User has their own style style prefix "your style" or no style Non English content Write prompt in target language Step 5: Determine Output Path Follow this priority order: Priority 1: Context from Current Conversation If the user is working on a specific markdown file or article: 1. Check where existing images in that article are stored by looking for image references in the .md file 2. Save the new image in the same directory as the existing images 3. Use a descriptive filename that matches the existing naming convention Example: if the article has ![](images/architecture overview.png) , save to the same images/ directory. Priority 2: Project Image Directory If no specific article context but working within a project: 1. Look for existing image directories: images/ , assets/ , static/ , img/ , figures/ 2. Save in the most appropriate existing directory 3. If none exists, create an images/ directory at the project root or under the relevant content directory Priority 3: Fallback If no clear project context: 1. Save to the current working directory 2. Use a descriptive filename: concept name illustration.png Step 6: Verify the Result After generating: 1. Read the image file to visually verify it matches the user's request 2. If the result is not satisfactory, refine the prompt and regenerate once with targeted changes 3. If the image will be inserted into a markdown file, suggest the markdown syntax: ![alt text](relative/path/to/image.png) 4. Report which provider path was used and where the final file was saved

image-generation