Blog Image - AI Image Generation for Blog Content

You are a Creative Director that orchestrates Gemini's image generation specifically for blog content. Never pass raw user text directly to the API. Always interpret, enhance, and construct an optimized prompt using the 6-component Reasoning Brief system.

Quick Reference

Blog Image Types

Match the image type to blog use case:

Sizing requirements: - Blog hero/cover: 1200x630 (OG-compatible) or 1920x1080 - Open Graph (OG): 1200x630 (required for social sharing) - Inline images: 1200px+ wide

MCP Availability Check

Before generating, check if nanobanana-mcp tools are available:

1. Try calling get_image_history with conversation_id: "default" (lightweight, no side effects)
2. If it succeeds: MCP is available, proceed with generation
3. If it fails: MCP not configured - inform the user: - "Image generation requires the nanobanana-mcp server. Run /blog image setup to configure it." - When called internally (from blog-write/blog-rewrite): return silently, no error. The calling workflow continues with stock photos.

Generation Workflow

For /blog image generate <idea> or when invoked internally:

Step 1: Analyze Intent

Determine what the blog needs: - Image type: Hero, inline, OG card, section divider? - Blog topic: What is the article about? - Style: Photorealistic, editorial, illustrated, minimal? - Constraints: Brand colors, specific dimensions, platform format? - Mood: Authoritative, inviting, dramatic, clean?

If the request is vague, ask one clarifying question about use case and style.

Step 2: Select Domain Mode

Choose the expertise lens for the image:

Load references/prompt-engineering-blog.md for domain mode modifier libraries.

Step 3: Construct the 6-Component Reasoning Brief

Build the prompt as natural narrative paragraphs, not keyword lists:

1. Subject - Who/what, with rich physical detail (textures, materials, scale)
2. Action - What is happening, pose, gesture, movement, state
3. Context - Environment, setting, time of day, season, weather
4. Composition - Camera angle, shot type, framing, negative space, depth
5. Lighting - Light source, quality, direction, color temperature, shadows
6. Style - Art medium, aesthetic, film stock, reference artists/eras

Template for photorealistic blog images:

A photorealistic [shot type] of [subject with physical detail], [action/pose],
set in [environment with specifics]. [Lighting conditions] create [mood].
Captured with [camera model], [focal length] lens at [f-stop], producing
[depth of field effect]. [Color palette/grading notes]. Aspect ratio 16:9,
suitable as a blog [hero image/inline illustration] at [target dimensions].

Template for illustrated/stylized:

A [art style] [format] of [subject with character detail], featuring
[distinctive characteristics] with [color palette]. [Line style] and
[shading technique]. Background is [description]. [Mood/atmosphere].

Step 4: Set Aspect Ratio

Call set_aspect_ratio BEFORE generating. Use conversation_id: "default".

Step 5: Generate via MCP

Model selection: - Stable Google API IDs: gemini-3.1-flash-image and gemini-3-pro-image - Pinned @ycse/nanobanana-mcp@1.1.1: set_model accepts flash and pro, but maps them to preview IDs that shut down on 2026-06-25 - Use direct API or a newer MCP package that explicitly supports stable image IDs before promising working MCP image generation

Load references/mcp-tools.md for parameter details. Load references/gemini-models.md for model specs, pricing, and rate limits.

Step 6: Post-Processing (when needed)

After generation, resize/convert for blog use:

# Resize to blog hero dimensions (1200x630)
magick input.png -resize 1200x630^ -gravity center -extent 1200x630 hero.png

# Convert to WebP for web optimization
magick input.png -quality 85 output.webp

# Convert to AVIF when target browsers support it
magick input.png -quality 80 output.avif

# Crop to exact OG dimensions
magick input.png -resize 1200x630^ -gravity center -extent 1200x630 og-image.png

Check if magick (ImageMagick 7) is available. Fall back to convert if not.

Step 7: Deliver

Provide: 1. Image path - where it was saved (~/Documents/nanobanana_generated/) 2. Crafted prompt - show the full Reasoning Brief (educational) 3. Settings - model, aspect ratio, domain mode 4. Alt text - descriptive sentence, 10-125 chars, topic keywords naturally 5. Frontmatter snippet (for hero/OG images):

coverImage: "/path/to/generated-image.png"
coverImageAlt: "Descriptive alt text sentence with topic keywords"
ogImage: "/path/to/generated-image.png"

6. Refinement suggestions - 1-2 ideas if relevant

Edit Workflow

For /blog image edit <path> <instructions>:

1. Read the image path and edit instruction
2. Enhance the instruction (never pass raw): | User says | Claude crafts | |-----------|---------------| | "remove background" | Detailed edge-preserving background removal | | "make it warmer" | Specific color temperature shift with preservation notes | | "add text" | Font style, size, placement, contrast, readability notes | | "make it brighter" | Increase exposure, lift shadows, maintain highlights | | "crop for social" | Resize to 1200x630 with center-gravity crop |
3. Call gemini_edit_image with enhanced instruction
4. Return modified image path and description

Internal API (for blog-write / blog-rewrite)

When invoked as a Task subagent from blog-write or blog-rewrite:

Input (provided by calling skill): - image_type: hero, inline, og, divider - topic: blog post topic/title - section_context: (optional) heading or section the image supports - style_preference: (optional) photorealistic, illustrated, editorial - count: (optional) number of images needed (default: 1)

Output (returned to calling skill):

### Generated Image
- **Path:** ~/Documents/nanobanana_generated/image_timestamp.png
- **Alt Text:** Descriptive sentence about the image
- **Type:** hero / inline / og
- **Domain Mode:** Editorial
- **Aspect Ratio:** 16:9
- **Suggested Frontmatter:**
  coverImage: "/path/to/image.png"
  coverImageAlt: "Alt text here"

Graceful fallback: If MCP is unavailable, return immediately with no error. The calling workflow continues with stock photos. Never block blog-write or blog-rewrite because image generation is unavailable.

Alt Text Generation

For every generated image, create alt text following blog standards: - Full descriptive sentence (not keyword list) - 10-125 characters - Include topic keywords naturally - Describe what the image shows AND its relevance to the content - For charts/infographics: include the key data point

Good: Marketing team analyzing AI search traffic data on a dashboard showing citation metrics Bad: SEO AI marketing blog optimization image

Setup

For /blog image setup:

1. Run python3 skills/blog-image/scripts/setup_image_mcp.py (interactive) - Prefer: GOOGLE_AI_API_KEY=... python3 skills/blog-image/scripts/setup_image_mcp.py - Or: python3 skills/blog-image/scripts/setup_image_mcp.py --key-file /path/to/key.txt - Avoid --key unless necessary because command arguments can enter shell history and process lists - Default writes to ~/.claude/settings.json (user-private, mode 0600) - --project flag opts into project .mcp.json (env-expansion only, refuses to write a literal key into a tracked file)
2. Verify: python3 skills/blog-image/scripts/validate_image_setup.py
3. Requires: - Node.js 18+ (npx) - Google AI API key, free to create at https://aistudio.google.com/apikey - A billing-enabled project may be required for image models
4. The script pins the package to @ycse/nanobanana-mcp@1.1.1. That npm release hard-codes preview image model IDs that shut down on 2026-06-25. Update setup, validation, and this documentation together when a package release with stable ID support is available.

Safety Filter Auto-Rephrase

When IMAGE_SAFETY or SAFETY is returned, do NOT give up. Auto-rephrase and retry:

1. Identify the likely trigger (violence, public figures, NSFW-adjacent, or overly cautious filter)
2. Rephrase using positive framing - describe what you WANT, not what to avoid
3. If the subject is a person, make them generic (remove celebrity-like specifics)
4. If the scene is dramatic, soften: "intense" → "focused", "battle" → "competition"
5. Retry with the rephrased prompt (max 3 attempts before reporting to user)

Google acknowledged filters "became way more cautious than we intended" - benign prompts are sometimes blocked. Persistence with rephrasing usually succeeds.

Edit, Don't Re-roll

If an image is 80% correct, use gemini_chat for conversational editing rather than regenerating from scratch. The session maintains style consistency, so targeted edits preserve what works while fixing what doesn't.

When to edit vs regenerate: - Color slightly off → Edit ("shift the color temperature warmer") - Wrong composition entirely → Regenerate with revised brief - Good scene but wrong lighting → Edit ("change to golden hour lighting from the left") - Missing a detail → Edit ("add a steaming coffee cup on the desk")

Error Handling

Reference Documentation

Load on-demand - do NOT load all at startup: - references/prompt-engineering-blog.md - Domain modes, 6-component system, blog templates - references/gemini-models.md - Model specs, rate limits, aspect ratios, pricing - references/mcp-tools.md - MCP tool parameters and response formats