design-brief

What this skill does

# Design Brief Skill

Parse a structured design brief into a concrete DESIGN.md and optional visual preview. Agent, follow this workflow exactly.

## Background

The 8 dimensions in this skill are derived from analysis of the 71 design systems bundled with Open Design. Every DESIGN.md in `design-systems/` resolves at minimum: color palette, accent, typography, display font, layout model, and component style. We distilled these into 8 orthogonal dimensions that cover the decisions a designer makes before any pixel is placed. Mood and density were added because they are the two most common sources of ambiguity in natural language briefs ("make it clean" means different things to different people).

Dimensions intentionally excluded from the brief level: animation timing, responsive strategy, and accessibility contrast. These are enforced at the template level by individual skills (e.g., `saas-landing` handles its own responsive logic), though the generated DESIGN.md includes sensible breakpoint defaults for downstream consumption.

## 1. Accept input

The user provides a design brief in one of two formats:

### Option A: I-Lang structured brief

```
[PLAN:@DESIGN|type=saas_landing]
  |palette=navy_and_white|accent=coral
  |typography=inter|display=space_grotesk
  |layout=single_column|max_width=1200px
  |mood=professional_minimal
  |density=spacious|section_gap=96px
  |hero=headline+subhead+cta
  |sections=features,pricing,testimonials,footer
  |exclude=animations,parallax,gradients
  |responsive=mobile_first
```

### Option B: Natural language

> "I need a landing page for a developer tool. Clean, minimal, dark mode. Inter font. No flashy animations."

If the user provides Option B, convert it to the structured format using the mapping table below, then proceed. Identify every dimension explicitly stated and flag dimensions that were left unspecified.

### Natural language → I-Lang mapping

For each sentence in the natural language input, identify dimension keywords and map to the closest structured value:

| Natural language phrase | Dimension | I-Lang value |
|------------------------|-----------|-------------|
| "dark mode", "dark theme" | palette | `monochrome_dark` |
| "light", "white background" | palette | `light_clean` |
| "earthy", "warm tones" | palette | `earth_tones` |
| "pop of color", "vibrant" | accent | `electric_blue` (default) or `coral` |
| "subtle accent" | accent | `muted_sage` (default) or `slate` |
| "clean", "minimal", "simple" | mood | `professional_minimal` |
| "playful", "fun", "friendly" | mood | `playful` |
| "bold", "brutalist", "raw" | mood | `brutalist` |
| "editorial", "magazine-like" | mood | `editorial` |
| "spacious", "lots of whitespace" | density | `spacious` |
| "compact", "dense", "information-rich" | density | `compact` |
| "Inter", "system font" | typography | `inter` (default) or `system_ui` |
| "serif", "traditional" | typography | `georgia` (default) or `playfair` |
| "monospace", "code-like" | typography | `jetbrains_mono` |
| "no animations", "static" | exclude | `animations` |
| "no gradients" | exclude | `gradients` |
| "no stock photos" | exclude | `stock_photos` |
| "single page" | layout | `single_column` |
| "two columns", "sidebar" | layout | `two_column` |
| "mobile first" | responsive | `mobile_first` |

When a phrase maps to multiple dimensions (e.g. "clean dark landing page" → mood=professional_minimal + palette=monochrome_dark + layout=single_column), resolve each dimension independently. When multiple values are listed for a single mapping, the first is the default; the agent may select the alternative only if surrounding context strongly favors it.

## 2. Validate dimensions

Every design brief must resolve these 8 dimensions. If any are missing from the input, select sensible defaults using the rules in Section 2.2.

The values listed below form a closed vocabulary. Only values in this table have concrete token mappings in Section 2.1. If the user provides a value not listed here, the agent must prompt for clarification rather than guessing.

| # | Dimension | Key | Example values |
|---|-----------|-----|---------------|
| 1 | Color palette | `palette` | navy_and_white, earth_tones, monochrome_dark, light_clean |
| 2 | Accent color | `accent` | coral, electric_blue, emerald, muted_sage |
| 3 | Body typography | `typography` | inter, system_ui, dm_sans, georgia |
| 4 | Display typography | `display` | space_grotesk, clash_display, same_as_body, playfair |
| 5 | Layout model | `layout` | single_column, two_column, asymmetric |
| 6 | Mood | `mood` | professional_minimal, playful, brutalist, editorial |
| 7 | Density | `density` | compact, balanced, spacious |
| 8 | Constraints | `exclude` | animations, gradients, stock_photos, carousel |

### 2.1 Symbolic → concrete token resolution

Each symbolic value maps to concrete design tokens. The agent must resolve these before writing DESIGN.md:

| Symbolic value | Concrete tokens |
|---------------|----------------|
| `palette=navy_and_white` | Background: #0F172A, Surface: #1E293B, Text: #F8FAFC, Secondary: #94A3B8 |
| `palette=monochrome_dark` | Background: #09090B, Surface: #18181B, Text: #FAFAFA, Secondary: #A1A1AA |
| `palette=light_clean` | Background: #FFFFFF, Surface: #F8FAFC, Text: #0F172A, Secondary: #64748B |
| `palette=earth_tones` | Background: #FFFBEB, Surface: #FEF3C7, Text: #451A03, Secondary: #92400E |
| `accent=coral` | Accent: #F97316, Hover: #EA580C |
| `accent=electric_blue` | Accent: #3B82F6, Hover: #2563EB |
| `accent=emerald` | Accent: #10B981, Hover: #059669 |
| `accent=muted_sage` | Accent: #84A98C, Hover: #6B8F73 |
| `accent=slate` | Accent: #64748B, Hover: #475569 |
| `typography=inter` | Body: Inter, 400, 1rem/1.6 |
| `typography=system_ui` | Body: system-ui, 400, 1rem/1.6 |
| `typography=dm_sans` | Body: DM Sans, 400, 1rem/1.6 |
| `typography=georgia` | Body: Georgia, 400, 1.125rem/1.7 |
| `display=space_grotesk` | Display: Space Grotesk, 700, clamp(2rem, 5vw, 3.5rem) |
| `display=clash_display` | Display: Clash Display, 700, clamp(2rem, 5vw, 3.5rem) |
| `display=playfair` | Display: Playfair Display, 700, clamp(2rem, 5vw, 3.5rem) |
| `display=same_as_body` | Display inherits body font family, weight 600 |
| `density=compact` | Section spacing: 48px, Content padding: 16px/24px |
| `density=balanced` | Section spacing: 72px, Content padding: 24px/40px |
| `density=spacious` | Section spacing: 96px, Content padding: 24px/48px |

Symbolic values not in this table are not valid. If the user provides an unrecognized value (e.g., `palette=ocean_blue`), the agent must prompt for clarification: "I don't recognize `palette=ocean_blue`. Did you mean `navy_and_white`, `monochrome_dark`, `light_clean`, or `earth_tones`?"

### 2.2 Default resolution rules

When a dimension is unspecified, defaults are selected based on mood compatibility:

| Unspecified dimension | Default rule |
|----------------------|-------------|
| `palette` | If mood=editorial → `light_clean`. If mood=brutalist → `monochrome_dark`. Otherwise → `light_clean`. |
| `accent` | If palette is dark → `coral`. If palette is light → `electric_blue`. |
| `typography` | Always → `inter` (highest cross-platform legibility). |
| `display` | If mood=editorial → `playfair`. If mood=brutalist → `space_grotesk`. Otherwise → `same_as_body`. |
| `layout` | Always → `single_column` (safest responsive default). |
| `mood` | Always → `professional_minimal` (least opinionated). |
| `density` | Always → `balanced`. |
| `exclude` | Always → none (no constraints unless specified). |

If mood is also unspecified, all defaults fall back to the safe neutral set: `palette=light_clean`, `accent=electric_blue`, `typography=inter`, `display=same_as_body`, `layout=single_column`, `mood=professional_minimal`, `density=balanced`, `exclude=none`.

## 3. Generate DESIGN.md

This skill generates a new DESIGN.md from scratch based on the resolved brief dimensions. If a DESIGN.md already exists i