ext-apps/examples/customer-segmentation-server
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Olivier Chafik a0dcf16843 CI: build the WSL job on ext4, skip the unused Chromium download, list tsconfig types
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where the Linux job takes 23 s. The step now copies the tree onto the
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src feat: compile example servers to JavaScript for npm consumption (#259) 2026-01-14 23:46:17 +00:00
.gitignore Improve consistency and organization of examples for AI learning 2026-01-13 20:48:02 -06:00
grid-cell.png feat(basic-host): URL params, fullscreen mode, unified layout (#266) 2026-01-14 22:09:41 +00:00
main.ts refactor: finish MCP SDK v2 migration 2026-07-14 17:07:30 -07:00
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server.ts refactor: finish MCP SDK v2 migration 2026-07-14 17:07:30 -07:00
tsconfig.json CI: build the WSL job on ext4, skip the unused Chromium download, list tsconfig types 2026-09-08 18:38:58 +01:00
tsconfig.server.json CI: build the WSL job on ext4, skip the unused Chromium download, list tsconfig types 2026-09-08 18:38:58 +01:00
vite.config.ts Add customer-segmentation-server example 2025-12-04 14:32:47 -06:00

Example: Customer Segmentation Explorer

A demo MCP App that displays customer data as an interactive scatter/bubble chart with segment-based clustering. Users can explore different metrics, filter by segment, and click to see detailed customer information.

Account age vs revenue Tickets, NPS, engagement Age, engagement, revenue

MCP Client Configuration

Add to your MCP client configuration (stdio transport):

{
  "mcpServers": {
    "customer-segmentation": {
      "command": "npx",
      "args": [
        "-y",
        "--silent",
        "--registry=https://registry.npmjs.org/",
        "@modelcontextprotocol/server-customer-segmentation",
        "--stdio"
      ]
    }
  }
}

Local Development

To test local modifications, use this configuration (replace ~/code/ext-apps with your clone path):

{
  "mcpServers": {
    "customer-segmentation": {
      "command": "bash",
      "args": [
        "-c",
        "cd ~/code/ext-apps/examples/customer-segmentation-server && npm run build >&2 && node dist/index.js --stdio"
      ]
    }
  }
}

Features

  • Interactive Scatter Plot: Bubble chart visualization using Chart.js with configurable X/Y axes
  • Segment Clustering: 250 customers grouped into 4 segments (Enterprise, Mid-Market, SMB, Startup)
  • Axis Selection: Choose from 6 metrics for each axis (Revenue, Employees, Account Age, Engagement, Tickets, NPS)
  • Size Mapping: Optional bubble sizing by a third metric for additional data dimension
  • Legend Filtering: Click segment pills to show/hide customer groups
  • Detail Panel: Hover or click customers to see name, segment, revenue, engagement, and NPS
  • Theme Support: Adapts to light/dark mode preferences

Running

  1. Install dependencies:

    npm install
    
  2. Build and start the server:

    npm run start:http  # for Streamable HTTP transport
    # OR
    npm run start:stdio  # for stdio transport
    
  3. View using the basic-host example or another MCP Apps-compatible host.

Architecture

Server (server.ts)

Exposes a single get-customer-data tool that returns:

  • Array of 250 generated customer records with segment assignments
  • Segment summary with counts and colors for each group
  • Optional segment filter parameter

The tool is linked to a UI resource via _meta.ui.resourceUri.

App (src/mcp-app.ts)

  • Uses Chart.js bubble chart for the visualization
  • Fetches data once on connection
  • Dropdown controls update chart axes and bubble sizing
  • Custom legend with clickable segment toggles
  • Detail panel updates on hover/click interactions

Data Generator (src/data-generator.ts)

  • Generates realistic customer data with Gaussian clustering around segment centers
  • Each segment has characteristic ranges for revenue, employees, engagement, etc.
  • Company names generated from word-list combinations (e.g., "Apex Data Corp")
  • Data cached in memory for consistency across requests