claude ai mcp demo

Pop-up shop in a box. A themeable micro-storefront that Claude can rebrand and restock end-to-end through MCP — same site, swappable identity. "Make this an artisanal coffee roaster" → palette, fonts, hero, and product list all flip live. Then "actually, make it a vintage record store" → it flips again.

Built to show, at internal demos like Digital AI Sharing, that an MCP server can drive a website's content AND its look-and-feel — not just CRUD a row in a CMS.

What it shows

• Content control — Products collection exposed over the official @payloadcms/plugin-mcp, plus bulk tools (createManyProducts, updateManyProducts) with per-item transactions and partial success.

• Look-and-feel control (planned, see Status) — SiteSettings for theme tokens (palette, typography, brand) and Pages/Sections for hero/featured/footer blocks — all writable over MCP.

• Safety rails — every MCP write lands as a draft (forceDraftForMcpWrites hook) so a human can review before publish. MCP identity is a non-admin mcp-agents row, not a human admin.

• Two connection paths — paste a static API key (Claude Code, mcp-remote) OR connect via OAuth from Claude.ai web (WorkOS AuthKit as the authorization server).

Status

The themeable frontend and the site-config collections are the next chunk of work — that's the headline demo moment.

Setup

docker compose up -d                 # local Postgres on :5432
pnpm install
cp .env.example .env.local
# fill in PAYLOAD_SECRET — `openssl rand -hex 32`
# (WorkOS vars only needed for the Claude.ai web OAuth path)
pnpm dev

Open http://localhost:3000/admin, create the first admin, then:

1. Create an mcp-agents row (admin → MCP Agents).

2. Create an MCP API key (admin → MCP API Keys) bound to that agent.

3. Tick the createManyProducts / updateManyProducts checkboxes on the API-key row (custom tools are off-by-default).

4. Connect from an MCP client to http://localhost:3000/api/mcp with the API key as a bearer token.

Migrating from the older mcp-products-demo setup? The DB was renamed (mcp_products_demo → claude_ai_mcp_demo). Run docker compose down -v to nuke the old volume, then docker compose up -d for a fresh DB.

The demo moment (target)

Once the themeable frontend lands, the showcase prompt is something like:

"Rebrand this site as Ember & Oat, a small-batch coffee roaster. Warm earth-tone palette, serif headings, friendlier copy. Replace the products with 5 single-origin beans, prices $18–24, with tasting-note descriptions."

Claude calls a handful of MCP tools (update SiteSettings, replace Sections, bulk-create Products), the dev server picks up the drafts on next reload, the site is a coffee shop. Re-prompt with a different niche → it's something else.

Stack

• Next.js 16 (App Router) + React 19

• Payload CMS 3.85 with Postgres adapter

• @payloadcms/plugin-mcp — Streamable HTTP at /api/mcp

• WorkOS AuthKit (optional) — OAuth authorization server for Claude.ai web connections

• pnpm + Docker Compose for local Postgres

Layout

app/
  (frontend)/        # public site — themeable storefront (WIP)
  (payload)/         # admin UI + /api/mcp endpoint
collections/         # Admins, MCPAgents, Products (+ SiteSettings/Pages soon)
lib/
  mcp-tools.ts       # createManyProducts, updateManyProducts
  categories.ts
payload.config.ts    # plugin wiring, MCP_ENABLED kill switch