promptor

name: promptor description: > Generates optimized Nano Banana 2 (Gemini 3.1) image generation prompts from context. Specializes in ecommerce product photography, marketing visuals, social media graphics, and print-on-demand graphic design (t-shirts, mugs, posters, wall art, phone cases).

Use this skill whenever the user wants to create, generate, make, or design any visual content for products, shops, listings, social media, ads, or marketing. Triggers on mentions of: design a t-shirt, create product images, make a poster, generate graphics, POD design, etsy listing image, instagram post design, facebook ad image, product hero shot, mug design, wall art, phone case design, marketing banner, brand assets, packaging mockup, lifestyle photography prompt, infographic design. Also triggers when users mention Nano Banana, Gemini image generation, or need an AI image prompt for any commercial purpose.

Even if the user doesn't explicitly say "prompt" — if they're talking about creating any visual/graphic/design for a product or marketing context, this skill applies.

Nano Banana 2 Promptor

Generate optimized image generation prompts for Nano Banana 2 (Gemini 3.1) from natural conversation context. The skill analyzes what the user wants, applies design intelligence, and outputs a structured JSON prompt ready to paste into Nano Banana 2.

Why This Skill Exists

Nano Banana 2 is a thinking model — it understands creative intent, physics, and composition. It responds dramatically better to narrative descriptions than keyword lists. This skill bridges the gap between what users want ("a cool t-shirt design") and what Nano Banana 2 needs (a richly detailed, design-informed narrative prompt).

Core Pipeline

1. CONTEXT PARSER  → detect/infer dimensions from any input format
2. CATEGORY ROUTER → POD path or Commercial path
3. PROMPT COMPOSER → narrative prompt with design intelligence
4. JSON OUTPUT     → structured output ready for use

Step 1: Parse Context

Accept ANY input format — free-form text, structured fields, or minimal keywords. Extract these 8 dimensions:

10 Supported Categories

Style Inference

When the user provides no style direction, infer the optimal style from context:

For POD categories — read references/niche-modules.md and select the closest niche module based on subject + audience. The niche module defines typography, color, composition, and motif rules. If no niche fits cleanly, default to the niche that best matches the audience's identity signal.

For commercial categories — default to clean, professional photography aesthetic with modern composition. Match platform conventions (Instagram = vibrant/scroll-stopping, LinkedIn = professional, Pinterest = aspirational).

Step 2: Route by Category

POD Path (pod_tshirt, pod_mug, pod_poster, pod_accessories)

For POD categories, apply design intelligence from the reference files:

1. Read references/niche-modules.md — select the matching niche module and apply its rules for color limits, negative space targets, typography, composition, and motifs
2. Read references/design-principles.md — apply core design philosophy principles
3. Generate a mini design philosophy (2-3 sentences) — a poetic aesthetic direction inspired by the subject/audience that guides the visual tone. Think of it as naming a tiny art movement. Example: "Neon Nostalgia — vivid retro-futurism meets handcrafted warmth, where each element appears labored over with master-level care."
4. Apply the One Idea Principle — the design must communicate exactly ONE thing. If the context implies multiple competing ideas, distill to the strongest single concept.
5. Set background rule — Nano Banana 2 cannot generate transparent backgrounds. Instead:
   • If design is predominantly dark → use pure solid white background (#FFFFFF)
   • If design is light/colorful → use pure solid black background (#000000)
   • Always add: "clean isolated background with sharp edges, no gradients, no ambient shadows, no noise — optimized for AI background removal"

Commercial Path (product_hero, lifestyle, social_media, marketing_banner, infographic, logo_brand)

For commercial categories, apply Nano Banana 2 prompting best practices:

1. Read references/prompt-patterns.md — select camera specs, lighting setups, and composition patterns for the category
2. Set platform-specific aspect ratio:
   • Instagram feed: 4:5
   • Instagram story / TikTok: 9:16
   • Facebook ad: 1:1 or 4:5
   • Pinterest: 2:3
   • Web banner: 16:9 or 21:9
   • Email header: 3:1
   • General: 4:3 or 16:9
3. For product_hero — add camera hardware language (e.g., "Sony A7III, 85mm f/1.4, studio softbox lighting") as this dramatically improves photorealistic output
4. For marketing_banner — reserve negative space for text overlay, describe composition zones explicitly
5. For lifestyle — add environmental storytelling, atmospheric lighting, contextual props

Step 3: Compose the Prompt

Assemble a narrative-style prompt (not keyword lists). Nano Banana 2 is a thinking model — it performs dramatically better with descriptive paragraphs that explain creative intent.

Prompt Formula

[STYLE DECLARATION] + [SUBJECT DESCRIPTION] + [SETTING/ENVIRONMENT] +
[COMPOSITION & HIERARCHY] + [LIGHTING] + [TYPOGRAPHY if any] +
[TECHNICAL SPECS] + [CONSTRAINTS]

Writing Rules

• Narrative over keywords: "Create a dark gothic illustration of a highly detailed skull intertwined with blooming roses" beats "skull, roses, gothic, dark, detailed, illustration"
• Specific over vague: "weathered ceramic coffee mug with visible glaze cracks" beats "old mug"
• Camera language for realism: Include lens focal length, aperture, camera model when photorealistic output is needed
• Film stock as shorthand: "Shot on Kodak Portra 400" triggers warm tones + fine grain
• Text in quotes: Any text to render in the image must be wrapped in quotation marks with font description: "STAY WILD" in bold condensed sans-serif font, ALL-CAPS
• Design hierarchy language: Describe what the viewer sees first, second, third — this maps to the three-level visual hierarchy (primary 40-60%, secondary 25-35%, tertiary 15-25%)
• Craftsmanship emphasis: For POD designs, include language like "meticulously crafted", "painstaking attention to detail", "master-level execution" — this pushes Nano Banana 2 toward higher quality output
• Prompt length: Aim for 100-250 words. Enough detail to guide the model, not so much that it gets confused.

Anti-Pattern Guards

Before finalizing the prompt, verify it does NOT contain:

• Multiple competing focal points with no hierarchy (the "Shouting Match")
• More elements than the niche allows (the "Kitchen Sink")
• Keyword-stuffed quality modifiers like "4k, ultra HD, masterpiece, best quality" (Nano Banana 2 ignores these; use narrative instead)
• Requests for transparent backgrounds (not supported — use solid bg)
• Conflicting style directions ("vintage but also modern and futuristic")

Step 4: Output JSON

Always output in this exact structure:

{
  "context_analysis": {
    "detected": {
      "subject": "what was explicitly stated",
      "category": "detected category",
      "audience": "detected or null",
      "purpose": "detected or null",
      "style_hints": "detected or null",
      "text_content": "detected or null",
      "brand_voice": "detected or null",
      "constraints": ["detected constraints"]
    },
    "inferred": {
      "niche_module": "selected niche or null (POD only)",
      "color_system": "inferred palette description",
      "composition_template": "selected composition approach",
      "negative_space_target": "percentage",
      "typography_style": "font direction if applicable",
      "aspect_ratio": "W:H",
      "resolution": "4K",
      "background": "solid black/white + reasoning (POD only)"
    },
    "design_philosophy": "2-3 sentence mini art movement (POD only, null for commercial)"
  },
  "prompt_components": {
    "style": "visual style declaration",
    "subject": "detailed subject description",
    "setting": "environment/background description",
    "composition": "layout, hierarchy, eye flow",
    "typography": "text rendering instructions or null",
    "lighting": "lighting setup description",
    "technical": "aspect ratio, resolution, background",
    "constraints": "what to avoid"
  },
  "assembled_prompt": "The complete, ready-to-use narrative prompt combining all components into flowing paragraphs. This is what gets pasted directly into Nano Banana 2.",
  "metadata": {
    "model_target": "nano_banana_2",
    "aspect_ratio": "W:H",
    "resolution": "4K",
    "category": "the category",
    "niche_module": "if applicable",
    "design_rules_applied": ["list of rules that shaped this prompt"]
  }
}

Reference Files

These contain detailed domain knowledge. Read them as needed based on the category:

references/niche-modules.md

Read when: category is any POD type Contains: 10 niche modules (streetwear premium, streetwear hype, anime, rock/metal, hip-hop, skate/surf, vintage/retro, luxury gothic, pop culture, minimalist) with specific rules for typography, color limits, negative space, composition, motifs, and production. Also contains the niche selection decision tree.

references/prompt-patterns.md

Read when: any category (but especially commercial path) Contains: Nano Banana 2 specific prompting formulas, camera/lens specifications by category, lighting setups, platform aspect ratios, text rendering rules, and example prompts for each category.

references/design-principles.md

Read when: category is any POD type Contains: The design philosophy generation system, core mindset rules, visual hierarchy framework, composition systems, anti-patterns with diagnoses, and the One Idea Principle. Distilled from validated streetwear brand analysis.

Important Reminders

• Nano Banana 2 is a THINKING model. Write prompts that explain intent, not just list attributes.
• For POD: always use solid background (black or white) for easy AI removal. Never say "transparent background."
• The assembled_prompt should be a cohesive narrative, not a concatenation of the components.
• Quality comes from specificity and design intelligence, not from quality modifier keywords.
• When in doubt about style, lean toward strategic restraint — "premium design whispers, amateur design shouts."