Raven MCP

Odin's ravens brought back knowledge of the world — Raven brings back design intelligence.

A design knowledge MCP server that Claude can query when generating UI. Eight layers: principles, patterns, content design systems, research methods, service design, brand/visual, business strategy, and design tokens.

What it does

Raven gives Claude access to a comprehensive design knowledge base:

• Principles — Nielsen's 10 Heuristics, all 21 Laws of UX, Gestalt principles, WCAG accessibility, typography rules, color theory, mobile UX, D4D framework, UX writing, service design, and brand
• Patterns — Proven UI patterns for signup flows, pricing pages, navigation, forms, landing pages, dashboards, modals, empty/error/loading states, CTAs, social proof, mobile conversion — plus content patterns (error messages, empty-state copy, notifications, form validation) and service patterns (service blueprinting, human handoff, signup-as-service, omnichannel continuity, moments of truth)
• Content systems — Voice & tone guides from real brands: Mailchimp, GOV.UK, Shopify Polaris, Atlassian, and Intuit
• Research — Qualitative, quantitative, and usability methods with do/don't protocols and checklists. Metrics frameworks: HEART, AARRR/Pirate, North Star Metric, conversion funnel, RICE, OKRs.
• Service design — Service blueprinting (with HTML blueprint generation — current vs. ideal state), human-handoff patterns, signup-as-service, omnichannel continuity, moments of truth / recovery, and the GOV.UK Service Standard
• Brand & visual — Logo usage (clear space, min sizes, variants, placement, restraint), gradient usage (hierarchy, palette, contrast, trend vs signature), imagery (consistency, representation, purpose), visual hierarchy, brand-as-system, and current (2026) visual-design trends
• Business — Monetization models, retention strategies, onboarding optimization, growth mechanics, and product metrics frameworks
• Tokens — Design system tokens for Stripe, Linear, and more

Install

Claude Code — one command

claude mcp add raven -- npx -y raven-mcp

Manual config (Claude Desktop or team .mcp.json)

{
  "mcpServers": {
    "raven": {
      "command": "npx",
      "args": ["-y", "raven-mcp"]
    }
  }
}

Claude Desktop — one-click extension

Prefer not to edit JSON? Download raven.mcpb and double-click it. Claude Desktop installs Raven automatically — no Node, no terminal.

From source

git clone https://github.com/rhinocap/raven-mcp.git
cd raven-mcp && npm install && npm run build

Tools

| Tool | Description | |------|-------------| | get_principles | Get design principles relevant to a UI context | | get_pattern | Get proven patterns for a specific UI type | | get_business_strategy | Get business/monetization strategies | | evaluate_design | Evaluate a design description against principles | | search_knowledge | Search across all principles, patterns, and strategies | | get_checklist | Get a pre-publish checklist for a UI type | | get_d4d_framework | Get Design for Delight framework templates | | list_design_systems | Browse available design systems | | get_design_system | Get tokens for a specific design system | | compose_system | Mix tokens from different systems | | get_brand_system | Get a full system styled like a well-known brand | | audit_page | Audit HTML/CSS against Raven's quality standards | | audit_layout | Evaluate visual rhythm, alignment, and optical balance | | generate_design_system | Generate a custom design system from a brand color | | list_content_systems | Browse brand voice & tone systems (Mailchimp, GOV.UK, Shopify Polaris, Atlassian, Intuit) | | get_content_system | Get a brand's voice attributes, tone shifts, vocabulary, grammar, and content patterns | | get_content_principles | Get UX-writing principles — clarity, active voice, error anatomy, inclusive language | | get_content_pattern | Get copy recipes for error messages, empty-state copy, notifications, form validation | | get_research_method | Get qualitative, quantitative, or usability research methods with protocols and checklists | | get_metrics_framework | Get a product-metrics framework — HEART, AARRR, North Star, conversion funnel, RICE, OKRs | | get_service_pattern | Get a service design pattern — blueprinting, human handoff, signup-as-service, omnichannel, moments of truth | | get_service_standard | Get the GOV.UK Service Standard — 14 points for evaluating service quality | | generate_service_blueprint | Render a service blueprint as HTML — current state, or current vs. ideal side-by-side | | get_brand_principles | Get brand/visual principles — logo, gradient, imagery, hierarchy, brand-as-system | | get_brand_trends | Get current (2026) brand and visual-design trends with usage guidance | | raven_reflect | Summarize your local Raven usage log to find patterns + gaps |

Release updates

Raven ships new principles, patterns, and brand systems regularly. For one email per minor/major release (patches stay quiet):

• Web: ravenmcp.ai/#updates — 10 seconds, one email field.
• In-product: ask Claude "register me for Raven updates at [email protected]" — Claude calls raven_register and you're in.

No marketing, unsubscribe anytime. Powered by Resend.

Learning loop

Raven keeps a small local-only log of how you use it so you (and Claude) can spot which patterns you build most often and which gaps show up again and again.

• Location: ~/.raven/usage.jsonl (override with RAVEN_USAGE_LOG=/path).
• What's written: tool name, timestamp, elapsed ms, and a tiny insight object — audit score/warning rule names, pattern type, brand company name, search layer. Never the HTML you audit, never prompt text, never brand copy.
• What's never written: raw page bodies, client content, your work product.
• Disable entirely: RAVEN_NO_USAGE_LOG=1.
• Reflect: ask Claude "what have I been using Raven for?" and it will call raven_reflect, which reads the log locally and summarizes the last N days — most-used tools, recurring audit warnings (likely knowledge gaps), patterns you request most, design systems you reach for.

Nothing is sent to a remote server. If a recurring gap is worth turning into a new Raven principle or pattern, you file an issue by hand — the automated pipeline at github.com/rhinocap/raven-mcp handles it from there.

Development

npm run dev    # Run with tsx (hot reload)
npm run build  # Compile TypeScript
npm start      # Run compiled output

Data structure

All knowledge lives in src/data/ as static JSON files:

src/data/
  principles/      # Nielsen, Laws of UX, Gestalt, accessibility, typography, color, mobile, D4D
  patterns/        # signup, pricing, nav, forms, landing, dashboard, modals, empty/error/loading, CTA, social proof, mobile
  business/        # monetization, retention, onboarding, growth, metrics
  tokens/          # registry.json + systems/ (stripe, linear, vercel, …)
  content/         # voice & tone: Mailchimp, GOV.UK, Shopify Polaris, Atlassian, Intuit
    systems/       # registry.json + brand-voice JSONs
    principles/    # UX-writing principles (clarity, active voice, error anatomy, …)
    patterns/      # copy recipes for errors, empty states, notifications, form validation
  research/        # study protocols + metrics frameworks
    principles/    # research fundamentals (method match, bias, sample size, ethics, triangulation, …)
    methods/       # qualitative, quantitative, usability
    frameworks/    # HEART, AARRR, North Star, conversion funnel, RICE, OKRs
  service-design/  # service-level principles + patterns + frameworks
    principles/    # Stickdorn, Shostack, peak-end, moments of truth, handoff
    patterns/      # service blueprinting, human handoff, signup-as-service, omnichannel, moments of truth
    frameworks/    # GOV.UK Service Standard (14 points)
  brand/           # brand & visual design
    principles/    # logo, gradient, imagery, hierarchy, brand-as-system
    trends/        # 2026-current.json