# Prompt Writing Guide

Tips for writing effective image generation prompts, tailored to each provider.

## OpenAI (natural language)

OpenAI models work best with natural language descriptions. Be specific about what you want.

### General tips

- Describe the scene in complete sentences
- Include style, lighting, and composition details
- Specify camera angle or perspective when relevant
- Mention the medium (photograph, oil painting, digital art, etc.)

### Examples

**Product photography:**

```
A professional product photo of white sneakers on a clean white background,
studio lighting, sharp focus, commercial photography style, high resolution
```

**Logo design:**

```
A minimalist logo for "Acme Corp" with clean sans-serif typography,
blue and white color scheme, modern design, vector art style
```

**Illustration:**

```
A whimsical children's book illustration of a fox reading a book under
a large oak tree, watercolor style, warm autumn colors, soft lighting
```

### Negative prompts

When using OpenAI, negative prompts are appended as an "Avoid:" clause. Keep them concise:

```
Avoid: blurry, low quality, distorted text, watermark
```

---

## A1111 / Stable Diffusion (CLIP tag format)

Stable Diffusion models respond best to comma-separated tags ordered by importance.

### Tag structure

```
subject, medium, style, lighting, camera, quality tags
```

### Examples

**Portrait:**

```
1girl, long hair, blue eyes, school uniform, standing, cherry blossoms,
soft lighting, detailed face, masterpiece, best quality
```

**Landscape:**

```
mountain landscape, sunset, dramatic clouds, lake reflection,
cinematic lighting, wide angle, 8k, highly detailed
```

**Product shot:**

```
white sneakers, product photography, studio lighting, white background,
sharp focus, commercial photography, high resolution
```

**Anime:**

```
1boy, silver hair, red eyes, dark coat, standing on rooftop, city skyline,
night, wind, detailed, anime style, masterpiece
```

### Weighted tokens (emphasis)

Use parentheses to increase or decrease emphasis on specific tokens:

```
# Increase emphasis (1.1x per level of parentheses)
(detailed face)       # 1.1x emphasis
((detailed face))     # 1.21x emphasis
(detailed face:1.5)   # 1.5x emphasis (explicit weight)

# Decrease emphasis
[blurry background]   # 0.9x emphasis
(blurry background:0.5)  # 0.5x emphasis (explicit weight)
```

Weights are relative to the baseline of 1.0. Values above 1.0 strengthen a concept; values below 1.0 weaken it. Extreme weights (above 1.8 or below 0.3) often produce artifacts.

### Quality tags

Add these to improve output quality:

| Tags | Effect |
|------|--------|
| `masterpiece, best quality` | General quality boost |
| `highly detailed, sharp focus` | Detail enhancement |
| `8k, ultra high res` | Resolution boost (use sparingly) |
| `professional, award winning` | Style refinement |

### Negative prompts

Always include a negative prompt with A1111 to avoid common artifacts.

**General-purpose:**

```
lowres, bad anatomy, bad hands, text, error, missing fingers,
extra digit, fewer digits, cropped, worst quality, low quality,
normal quality, jpeg artifacts, signature, watermark, blurry
```

**Add for photorealism:**

```
cartoon, anime, illustration, painting, drawing, art, sketch
```

**Add for anime/illustration:**

```
photo, realistic, 3d render
```

### BREAK syntax

Use `BREAK` to separate concepts into different CLIP token chunks. This is useful when your prompt is long or has distinct elements:

```
1girl, detailed face, blue eyes BREAK
forest background, sunlight through trees BREAK
masterpiece, best quality, sharp focus
```

### CLIP token limits

- **SD 1.5:** 77 tokens per CLIP chunk
- **SDXL:** 77 tokens per chunk, but uses two CLIP encoders (ViT-L + ViT-bigG)

Front-load the most important tags -- tokens beyond the first 77-token chunk have diminishing influence.

---

## Provider-agnostic tips

### Aspect ratios

All providers support these aspect ratios:

| Ratio | Best for |
|-------|----------|
| `1:1` | Avatars, icons, social media posts |
| `16:9` | Landscapes, banners, desktop wallpapers |
| `9:16` | Phone wallpapers, stories, portraits |
| `3:2` | Photography standard, prints |
| `2:3` | Book covers, posters |

### Common use cases

| Use case | Recommended provider | Prompt approach |
|----------|---------------------|-----------------|
| Logo with text | OpenAI | Natural language, specify text content exactly |
| Photo-realistic portrait | A1111 | Tag format, include quality and lighting tags |
| Anime character | A1111 | Tag format, include character details |
| Quick placeholder | Placeholder | Any prompt (generates solid color) |
| Product photo | A1111 or OpenAI | Describe studio setup and product details |
| Landscape art | A1111 or OpenAI | Include composition, lighting, and style |
