# Prompt Engineering Reference: Claude Banana

> Load this on-demand when constructing complex prompts or when the user
> asks about prompt techniques. Do NOT load at startup.
>
> Aligned with Google's March 2026 "Ultimate Prompting Guide" for Gemini image generation.

## The 6-Component Reasoning Brief

Every image prompt should contain these components, written as natural
narrative paragraphs, NEVER as comma-separated keyword lists.

### 1. Subject
The main focus of the image. Describe with physical specificity.

**Good:** "A weathered Japanese ceramicist in his 70s, deep sun-etched
wrinkles mapping decades of kiln work, calloused hands cradling a
freshly thrown tea bowl with an irregular, organic rim"

**Bad:** "old man, ceramic, bowl"

### 2. Action
What is happening. Movement, pose, gesture, state of being.

**Good:** "leaning forward with intense concentration, gently smoothing
the rim with a wet thumb, a thin trail of slip running down his wrist"

**Bad:** "making pottery"

### 3. Context
Environment, setting, temporal and spatial details.

**Good:** "inside a traditional wood-fired anagama kiln workshop,
stacked shelves of drying pots visible in the soft background, late
afternoon light filtering through rice paper screens"

**Bad:** "workshop, afternoon"

### 4. Composition
Camera angle, shot type, framing, spatial relationships.

**Good:** "intimate close-up shot from slightly below eye level,
shallow depth of field isolating the hands and bowl against the
soft bokeh of the workshop behind"

**Bad:** "close up"

### 5. Lighting
Light source, quality, direction, temperature, shadows.

**Good:** "warm directional light from a single high window camera-left,
creating gentle Rembrandt lighting on the face with a soft triangle
of light on the shadow-side cheek, deep warm shadows in the workshop"

**Bad:** "natural lighting"

### 6. Style
Art medium, aesthetic reference, technical photographic details.

**Good:** "captured with a Sony A7R IV, 85mm f/1.4 GM lens, Kodak Portra
400 color grading with lifted shadows and muted earth tones, reminiscent
of Dorothea Lange's documentary portraiture"

**Bad:** "photorealistic, 8K, masterpiece"

## Domain Mode Modifier Libraries

### Cinema Mode
**Camera specs:** RED V-Raptor, ARRI Alexa 65, Sony Venice 2, Blackmagic URSA
**Lenses:** Cooke S7/i, Zeiss Supreme Prime, Atlas Orion anamorphic
**Film stocks:** Kodak Vision3 500T (tungsten), Kodak Vision3 250D (daylight), Fuji Eterna Vivid
**Lighting setups:** three-point, chiaroscuro, Rembrandt, split, butterfly, rim/backlight
**Shot types:** establishing wide, medium close-up, extreme close-up, Dutch angle, overhead crane, Steadicam tracking
**Color grading:** teal and orange, desaturated cold, warm vintage, high-contrast noir

### Product Mode
**Surfaces:** polished marble, brushed concrete, raw linen, acrylic riser, gradient sweep
**Lighting:** softbox diffused, hard key with fill card, rim separation, tent lighting, light painting
**Angles:** 45-degree hero, flat lay, three-quarter, straight-on, worm's-eye
**Style refs:** Apple product photography, Aesop minimal, Bang & Olufsen clean, luxury cosmetics

### Portrait Mode
**Focal lengths:** 85mm (classic), 105mm (compression), 135mm (telephoto), 50mm (environmental)
**Apertures:** f/1.4 (dreamy bokeh), f/2.8 (subject-sharp), f/5.6 (environmental context)
**Pose language:** candid mid-gesture, direct-to-camera confrontational, profile silhouette, over-shoulder glance
**Skin/texture:** freckles visible, pores at macro distance, catch light in eyes, subsurface scattering

### Editorial/Fashion Mode
**Publication refs:** Vogue Italia, Harper's Bazaar, GQ, National Geographic, Kinfolk
**Styling notes:** layered textures, statement accessories, monochromatic palette, contrast patterns
**Locations:** marble staircase, rooftop at golden hour, industrial loft, desert dunes, neon-lit alley
**Poses:** power stance, relaxed editorial lean, movement blur, fabric in wind

### UI/Web Mode
**Styles:** flat vector, isometric 3D, line art, glassmorphism, neumorphism, material design
**Colors:** specify exact hex or descriptive palette (e.g., "cool blues #2563EB to #1E40AF")
**Sizing:** design at 2x for retina, specify exact pixel dimensions needed
**Backgrounds:** transparent (request solid white then post-process), gradient, solid color

### Logo Mode
**Construction:** geometric primitives, golden ratio, grid-based, negative space
**Typography:** bold sans-serif, elegant serif, custom lettermark, monogram
**Colors:** max 2-3 colors, works in monochrome, high contrast
**Output:** request on solid white background, post-process to transparent

### Landscape Mode
**Depth layers:** foreground interest, midground subject, background atmosphere
**Atmospherics:** fog, mist, haze, volumetric light rays, dust particles
**Time of day:** blue hour (pre-dawn), golden hour, magic hour (post-sunset), midnight blue
**Weather:** dramatic storm clouds, clearing after rain, snow-covered, sun-dappled

### Infographic Mode
**Layout:** modular sections, clear visual hierarchy, bento grid, flow top-to-bottom
**Text:** use quotes for exact text, descriptive font style, specify size hierarchy
**Data viz:** bar charts, pie charts, flow diagrams, timelines, comparison tables
**Colors:** high-contrast, accessible palette, consistent brand colors

### Abstract Mode
**Geometry:** fractals, voronoi tessellation, spirals, fibonacci, organic flow, crystalline
**Textures:** marble veining, fluid dynamics, smoke wisps, ink diffusion, watercolor bleed
**Color palettes:** analogous harmony, complementary clash, monochromatic gradient, neon-on-black
**Styles:** generative art, data visualization art, glitch, procedural, macro photography of materials

## Advanced Techniques

### Character Consistency (Multi-turn)
Use `gemini_chat` and maintain descriptive anchors:
- First turn: Generate character with exhaustive physical description
- Following turns: Reference "the same character" + repeat 2-3 key identifiers
- Key identifiers: hair color/style, distinctive clothing, facial feature

**Multi-image reference technique** (3.1 Flash):
- Provide up to 4-5 character reference images in the conversation
- Assign distinct names to each character ("Character A: the red-haired knight")
- Model preserves features across different angles, actions, and environments
- Works best when reference images show the character from multiple angles

### Style Transfer Without Reference Images
Describe the target style exhaustively instead of referencing an image:
```
Render this scene in the style of a 1950s travel poster: flat areas of
color in a limited palette of teal, coral, and cream. Bold geometric
shapes with visible paper texture. Hand-lettered title text with a
mid-century modern typeface feel.
```

### Text Rendering Tips
- Quote exact text: `with the text "OPEN DAILY" in bold condensed sans-serif`
- **25 characters or less**:this is the practical limit for reliable rendering
- **2-3 distinct phrases max**:more text fragments degrade quality
- Describe font characteristics, not font names
- Specify placement: "centered at the top third", "along the bottom edge"
- High contrast: light text on dark, or vice versa
- **Text-first hack:** Establish the text concept conversationally first ("I need a sign that says FRESH BREAD"), then generate. The model anchors on text mentioned early
- Expect creative font interpretations, not exact replication of described styles

### Positive Framing (No Negative Prompts)
Gemini does NOT support negative prompts. Rephrase exclusions:
- Instead of "no blur" → "sharp, in-focus, tack-sharp detail"
- Instead of "no people" → "empty, deserted, uninhabited"
- Instead of "no text" → "clean, uncluttered, text-free"
- Instead of "not dark" → "brightly lit, high-key lighting"

### Search-Grounded Generation
For images based on real-world data (weather, events, statistics),
Gemini can use Google Search grounding to incorporate live information.
Useful for infographics with current data.

**Three-part formula for search-grounded prompts:**
1. `[Source/Search request`:What to look up
2. `[Analytical task`:What to analyze or extract
3. `[Visual translation`:How to render it as an image

**Example:** "Search for the current top 5 programming languages by GitHub usage in 2026, analyze their relative popularity percentages, then generate a clean infographic bar chart with the language logos and percentages in a modern dark theme."

## Prompt Adaptation Rules

When adapting prompts from the claude-prompts database (Midjourney/DALL-E/etc.)
to Gemini's natural language format:

| Source Syntax | Gemini Equivalent |
|---------------|-------------------|
| `--ar 16:9` | Call `set_aspect_ratio("16:9")` separately |
| `--v 6`, `--style raw` | Remove - Gemini has no version/style flags |
| `--chaos 50` | Describe variety: "unexpected, surreal composition" |
| `--no trees` | Positive framing: "open clearing with no vegetation" |
| `(word:1.5)` weight | Descriptive emphasis: "prominently featuring [word]" |
| `8K, masterpiece, ultra-detailed` | Keep only "ultra-realistic, high resolution"; remove the rest |
| Comma-separated tags | Expand into descriptive narrative paragraphs |
| `shot on Hasselblad` | Keep - camera specs work well in Gemini |

## Common Prompt Mistakes

1. **Keyword stuffing**:stacking generic quality terms ("8K, masterpiece, best quality") adds nothing. Use only "ultra-realistic, high resolution" at the end
2. **Tag lists**:Gemini wants prose, not "red car, sunset, mountain, cinematic"
3. **Missing lighting**:The single biggest quality differentiator
4. **No composition direction**:Results in generic centered framing
5. **Vague style**:"make it look cool" vs specific art direction
6. **Ignoring aspect ratio**:Always set before generating
7. **Overlong prompts**:Diminishing returns past ~200 words; be precise, not verbose
8. **Text longer than ~25 characters**:Rendering degrades rapidly past this limit
9. **Burying key details at the end**:In long prompts, details placed last may be deprioritized; put critical specifics (exact text, key constraints) in the first third of the prompt
10. **Not iterating with follow-up prompts**:Use `gemini_chat` for progressive refinement instead of trying to get everything right in one generation

## Proven Prompt Templates

> Extracted from 2,500+ tested prompts. These patterns consistently produce
> high-quality results. Use them as starting points and adapt to the request.

### The Winning Formula (Weight Distribution)

| Component | Weight | What to include |
|-----------|--------|-----------------|
| **Subject** | 40% | Age, skin tone, hair color/style, eye color, body type, expression |
| **Styling** | 25% | Brand names, textures, fit, accessories, colors |
| **Environment** | 15% | Location + time of day + context details |
| **Camera** | 10% | Camera model + lens + focal length + shot type |
| **Lighting** | 10% | Quality, direction, color temperature, shadows |

### Instagram Ad / Social Media

**Pattern:** `[Subject with age/appearance] + [outfit with brand/texture] + [action verb] + [setting] + [camera spec] + [lighting] + [platform aesthetic]`

**Example (Product Placement):**
```
Hyper-realistic gym selfie of athletic 24yo influencer with glowing olive
skin, wearing crinkle-textured athleisure set in mauve. iPhone 16 Pro Max
front-facing portrait mode capturing sweat droplets on collarbones, hazel
eyes enhanced by gym LED lighting. Mirror reflection shows perfect form,
golden morning light through floor-to-ceiling windows. Frayed chestnut
ponytail with baby hairs, ultra-detailed skin texture, trending aesthetic.
```

**Example (Lifestyle Ad):**
```
A 24-year-old blonde fitness model in a high-energy sports drink
advertisement. Mid-run on a beach, wearing a vibrant orange sports bra
and black shorts, playful smile and sparkling blue eyes exuding vitality.
Bottle of the drink held in hand, waves crashing in background. Shot on
Nikon D850 with 70-200mm f/2.8 lens, natural light, fast shutter speed
capturing motion. Ultra-realistic skin texture, water droplets, product
label clearly visible.
```

**Example (Luxury Lifestyle):**
```
Gorgeous Instagram model wearing a designer silk gown, luxury rooftop
restaurant, golden hour lighting, champagne in hand, luxurious aspirational
lifestyle. Captured with Sony A7R IV, 85mm f/1.4 lens, shallow depth of
field, warm color grading.
```

### Product / Commercial Photography

**Pattern:** `[Product with brand/detail] + [dynamic elements] + [surface/setting] + "commercial photography for advertising campaign" + [lighting] + "high resolution"`

**Example (Beverage):**
```
Gatorade bottle with condensation dripping down the sides, surrounded by
lightning bolts and a burst of vibrant blue and orange light rays. The
Gatorade logo is prominently displayed on the bottle, with splashes of
water frozen in mid-air. Commercial food photography for an advertising
campaign, high resolution, high level of detail, vibrant complementary
colors.
```

**Example (Food):**
```
In and Out burger with layers of fresh lettuce, melted cheese, and pretzel
bun, placed on a white surface with the In and Out logo subtly glowing in
the background. Falling french fries and golden light, warm scene.
Commercial food photography for an advertising campaign, high resolution,
high level of detail, vibrant complementary colors.
```

### Fashion / Editorial

**Pattern:** `[Subject with ethnicity/age/features] + [outfit with texture/brand/cut] + [location] + [pose/action] + [camera + lens] + [lighting quality]`

**Example (Street Style):**
```
A 24-year-old female AI influencer posing confidently in an urban cityscape
during golden hour. Flawless sun-kissed skin, long wavy brown hair, deep
green eyes. Wearing a chic streetwear outfit: oversized beige blazer,
white top, high-waisted jeans. Captured with Sony A7R IV at 85mm f/1.4,
shallow depth of field with warm golden bokeh.
```

**Example (High Fashion):**
```
Stunning 24-year-old woman, long platinum blonde hair, radiant skin,
piercing blue eyes, dressed in a chic pastel blazer with a modern
minimalist aesthetic, soft sunlight glow, high-end fashion appeal.
Shot on Canon EOS R5, 85mm f/1.2 lens.
```

**Example (Avant-Garde):**
```
A blonde fitness model transformed into a runway-ready fashion icon,
wearing a bold avant-garde outfit: cropped leather jacket with neon pink
accents, paired with high-waisted athletic shorts and knee-high boots.
Captured mid-stride on a minimalist white runway, playful twinkle in her
eye, dramatic studio lighting from above.
```

### SaaS / Tech Marketing

**Pattern:** `[UI mockup or abstract visual] + "on [dark/light] background" + [specific colors with hex] + [typography description] + "clean, premium SaaS aesthetic" + [glassmorphism/gradient/glow effects]`

**Example (Dashboard Hero):**
```
A floating glassmorphism UI card on a deep charcoal background showing a
content analytics dashboard with a rising line graph in teal (#14B8A6),
bar charts in coral (#F97316), and a circular progress indicator at 94%.
Subtle grid lines, frosted glass effect with 20% opacity, teal glow
bleeding from the card edges. Clean premium SaaS aesthetic, no text
smaller than headline size.
```

**Example (Feature Highlight):**
```
An isometric 3D illustration of interconnected data nodes on a dark navy
background. Each node is a glowing teal sphere connected by thin luminous
lines, forming a constellation pattern. One central node pulses brighter
with radiating rings. Modern tech illustration style with subtle depth
of field, volumetric lighting from below.
```

**Example (Comparison/Before-After):**
```
Split-screen image: left side shows a cluttered, dim workspace with
scattered papers, red error indicators, and a frustrated expression
conveyed through a cracked coffee mug and tangled cables. Right side
shows a clean, organized dashboard interface glowing in teal and white
on a dark background, with smooth flowing lines and checkmarks. A sharp
vertical dividing line separates chaos from clarity.
```

### Logo / Branding

**Pattern:** `[Product/bottle/item] + "with [brand element] prominently displayed" + [dynamic visual elements] + "commercial photography" + [lighting style] + "high resolution, vibrant complementary colors"`

**Example:**
```
A sleek matte black bottle with a minimal white logo mark centered on the
label, surrounded by swirling gradient ribbons of teal and coral light.
The bottle sits on a reflective dark surface, sharp studio rim lighting
separating it from the background. Product photography for luxury
branding, high resolution, dramatic contrast.
```

### Key Tactics That Make Prompts Work

1. **Name real cameras**:"Sony A7R IV", "Canon EOS R5", "iPhone 16 Pro Max" anchor realism
2. **Specify exact lens**:"85mm f/1.4" gives the model precise depth-of-field information
3. **Use age + ethnicity + features**:"24yo with olive skin, hazel eyes" beats "a person"
4. **Name brands for styling**:"Lululemon mat", "Tom Ford suit" triggers specific visual associations
5. **Include micro-details**:"sweat droplets on collarbones", "baby hairs stuck to neck"
6. **Add platform context**:"Instagram aesthetic", "commercial photography for advertising"
7. **Describe textures**:"crinkle-textured", "metallic silver", "frosted glass"
8. **Use action verbs**:"mid-run", "posing confidently", "captured mid-stride"
9. **End with "ultra-realistic, high resolution"**:these two specific anchors help on Gemini. Avoid generic stacking like "8K, masterpiece, best quality" which adds no value
10. **For products, say "prominently displayed"**:ensures the product/logo isn't hidden

### Anti-Patterns (What NOT to Do)

- **"A dark-themed Instagram ad showing..."**:too meta, describes the concept not the image
- **"A sleek SaaS dashboard visualization..."**:abstract, no visual anchors
- **"Modern, clean, professional..."**:vague adjectives that mean nothing to the model
- **"A bold call to action with..."**:describes marketing intent, not visual content
- **Describing what the viewer should feel**:instead, describe what creates that feeling

## Safety Filter Rephrase Strategies

Gemini's safety filters (Layer 2: server-side output filter) cannot be disabled.
When a prompt is blocked, the only path forward is rephrasing.

### Common Trigger Categories

| Category | Triggers on | Rephrase approach |
|----------|------------|-------------------|
| Violence/weapons | Combat, blood, injuries, firearms | Use metaphor or aftermath: "battle-worn" → "weathered veteran" |
| Medical/gore | Surgery, wounds, anatomical detail | Abstract or clinical: "open wound" → "medical illustration" |
| Real public figures | Named celebrities, politicians | Use archetypes: "Elon Musk" → "a tech entrepreneur in a minimalist office" |
| Children + risk | Minors in any ambiguous context | Add safety context: specify educational, family, or playful framing |
| NSFW/suggestive | Revealing clothing, intimate poses | Use artistic framing: "fashion editorial, fully clothed, editorial pose" |

### Rephrase Patterns

1. **Abstraction**:Replace specific dangerous elements with abstract concepts
2. **Artistic framing**:Frame content as art, editorial, or documentary
3. **Metaphor**:Use symbolic language instead of literal descriptions
4. **Positive emphasis**:Describe what IS present, not what's dangerous
5. **Context shift**:Move from threatening to educational/professional context

### Example Rephrases

| Blocked prompt | Successful rephrase |
|----------------|---------------------|
| "a soldier in combat firing a rifle" | "a determined soldier standing guard at dawn, rifle slung over shoulder, morning mist over the outpost" |
| "a scary horror monster" | "a fantastical creature from a dark fairy tale, intricate organic textures, bioluminescent accents, concept art style" |
| "dog in a fight" | "a friendly golden retriever playing energetically in a sunny park, action shot, joyful expression" |
| "medical surgery scene" | "a clean modern operating room viewed from the observation gallery, soft blue surgical lights, professional documentary style" |
| "celebrity portrait of [name]" | "a distinguished middle-aged man in a tailored navy suit, warm studio lighting, editorial portrait style" |

### Key Principle

Layer 2 (output filter) analyzes the generated image, not just the prompt.
Even well-phrased prompts can be blocked if the model's interpretation triggers
the output filter. When this happens, try shifting the visual concept further
from the trigger rather than just changing words.