| name | design-system-author |
| description | Create or update a design system to the emdesign quality bar — author the 9-section DESIGN.md + tokens.css + base primitives. Use for the System flow (/mds:system:create | :update). Knows the four sources: brief, blank, import, extract. |
design-system-author
Authors the contract every project builds from. The richness of the DESIGN.md is the #1 lever on output
quality (see docs/authoring-design-systems.md).
Sources
- brief — turn a prompt ("warm editorial, serif display, terracotta accent") into a full system.
- blank — fill the scaffolded skeleton.
- import — start from a prebuilt base and customize. Call
list_design_system_bases (or
emdesign ds bases) to see the catalog of vendored open-design systems under
design-systems/_vendor/open-design/ (e.g. open-design/brutalist, open-design/editorial-burgundy),
pass its ref as from, then differentiate. Each base bundles its origin SKILL.md + reference assets.
- extract — infer tokens/voice from a brand/reference (pair with the
brand-extract skill).
Steps
- Scaffold via MCP
create_design_system({id,name,mode,from}) (skeleton DESIGN.md + base tokens.css +
manifest + base primitives copied in).
- Author the 9 sections to the bar: exact hex/rem/ms, a real type-scale table, per-component states,
and anti-patterns (each maps to a lint rule). Give the system an opinionated point of view (§1) and
a voice (§8).
- Re-value
tokens.css for every required role — semantic names only; keep it self-consistent.
- MCP
validate_design_system({id}) until the token contract passes (every role declared, every var()
resolves). Use /mds:system:create's design-system-loop to drive author→validate→refresh.
- Hand off:
/mds:system:use <id> to make it active, then the craft flow can build against it.
Guardrails
- Exact values + semantic roles + enforced anti-patterns. Vague prose → generic UI.
- Never leave a required token role undeclared;
validate_design_system is authoritative.
- Updating an existing system is high-blast-radius — assess
graph_find_affected first (see /mds:system:update).
