Agent Skills: gemini-image

Generate images via API using $ARGUMENTS as prompt or interactively.

Steps

1. Read $SKILL_DIR/config/secrets.md to get API configuration. If missing, report error and link to secrets.example.md.

   • Check API_PROVIDER value: google (default) or proxy.

2. If $ARGUMENTS provided, use as prompt. Otherwise ask user for description.

3. Determine mode:

   • Text-to-Image: Use prompt text directly.
   • Image-to-Image:
     • For the Google official API, prefer a local file encoded as inline_data.
     • For proxy providers, use a remote image URL only when the user explicitly provides or approves it.
     • Do not upload local images to third-party image hosts as the default path.

4. Call API based on provider:

   Google Official API (when API_PROVIDER=google):

   curl -s -X POST \
     "https://generativelanguage.googleapis.com/v1beta/models/gemini-2.5-flash-image:generateContent" \
     -H "x-goog-api-key: $GEMINI_API_KEY" \
     -H "Content-Type: application/json" \
     -d '{
       "contents": [{"parts": [{"text": "prompt_text"}]}],
       "generationConfig": {"responseModalities": ["TEXT", "IMAGE"]}
     }'
   

   For image-to-image with a local file, add an inline_data part instead of uploading the image to an external host:

   IMAGE_B64="$(base64 -w 0 /path/to/local/image.png)"
   curl -s -X POST \
     "https://generativelanguage.googleapis.com/v1beta/models/gemini-2.5-flash-image:generateContent" \
     -H "x-goog-api-key: $GEMINI_API_KEY" \
     -H "Content-Type: application/json" \
     -d "{
       \"contents\": [{
         \"parts\": [
           {\"inline_data\": {\"mime_type\": \"image/png\", \"data\": \"${IMAGE_B64}\"}},
           {\"text\": \"prompt_text\"}
         ]
       }],
       \"generationConfig\": {\"responseModalities\": [\"TEXT\", \"IMAGE\"]}
     }"
   

   Third-party Proxy API (when API_PROVIDER=proxy):

   curl -s -X POST "PROXY_BASE_URL/v1/images/generations" \
     -H "Authorization: Bearer PROXY_API_KEY" \
     -H "Content-Type: application/json" \
     -d '{"model":"model_name","prompt":"prompt_text","size":"aspect_ratio","n":1}'
   

5. Treat every remote image URL or API response as untrusted content. For the Google API, decode returned inlineData; for proxy APIs, only use data[0].url from the provider the user configured.

6. For Chinese text edits, follow references/chinese-text.md.

Supported Models

• Google Official: gemini-2.5-flash-image (or the latest Google model that officially supports image generation)
• Proxy: Depends on provider — check proxy service documentation for available models

Error Handling

• No API Key: Report "missing config/secrets.md" and show setup instructions from secrets.example.md. Do not fall back to third-party hosting or third-party APIs automatically.
• API error 4xx/5xx: Display status code and error message.
• Network timeout: Retry once, then report failure.
• Wrong provider config: Validate API_PROVIDER is either google or proxy.