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Filename Latest commit message Latest commit date
Olivier Chafik c3e9d4d694
 fix(examples): use server.registerTool for non-UI tool + fix missing imports (#173) 
* fix(threejs-server): use server.registerTool for non-UI tool

The learn_threejs tool doesn't have a UI component - it only returns
documentation text. Using registerAppTool without _meta causes a
runtime error when the function tries to access config._meta.ui.

Fixes crash: "Cannot read property 'ui' of undefined"

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude <noreply@anthropic.com>

* fix(examples): add missing registerAppTool and registerAppResource imports

All example servers were using registerAppTool and registerAppResource
but not importing them from @modelcontextprotocol/ext-apps/server,
causing "ReferenceError: registerAppTool is not defined" at runtime.

Affected servers:
- budget-allocator-server
- cohort-heatmap-server
- customer-segmentation-server
- scenario-modeler-server
- system-monitor-server
- threejs-server
- wiki-explorer-server

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude <noreply@anthropic.com>

---------

Co-authored-by: Claude <noreply@anthropic.com>
2025-12-17 00:17:45 +00:00
..
src refactor: rename request methods to remove send prefix (#161) 2025-12-16 22:07:06 +00:00
mcp-app.html Add color-scheme meta tag to all example apps 2025-12-15 11:42:18 -08:00
package.json feat: make MCP SDK a peer dependency (#168) 2025-12-16 22:09:59 +00:00
README.md Add wiki-explorer-server example (#122) 2025-12-11 13:58:05 +01:00
server.ts fix(examples): use server.registerTool for non-UI tool + fix missing imports (#173) 2025-12-17 00:17:45 +00:00
tsconfig.json Add wiki-explorer-server example (#122) 2025-12-11 13:58:05 +01:00
vite.config.ts Add wiki-explorer-server example (#122) 2025-12-11 13:58:05 +01:00

README.md

Example: Wiki Explorer

Visualizes Wikipedia link graphs using a force-directed layout. Explore how Wikipedia pages are connected by expanding nodes to reveal first-degree links.

Zoomed Pop-up Expanded graph

Features

  • Force-directed graph visualization: Interactive graph powered by force-graph
  • Node expansion: Click any node to expand and see all pages it links to
  • Visual state tracking: Nodes change color based on state (blue = default, green = expanded, red = error)
  • Direct page access: Open any Wikipedia page in your browser

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.

Tool Input

To test the example, call the get-first-degree-links tool with a Wikipedia URL:

{
  "url": "https://en.wikipedia.org/wiki/Graph_theory"
}

Click nodes in the graph to Open (view in browser) or Expand (visualize linked pages).

Architecture

Server (server.ts)

MCP server that fetches Wikipedia pages and extracts internal links.

Exposes one tool:

  • get-first-degree-links - Returns links to other Wikipedia pages from a given page

App (src/mcp-app.ts)

Vanilla TypeScript app using force-graph for visualization that:

  • Receives tool inputs via the MCP App SDK
  • Renders an interactive force-directed graph
  • Supports node expansion to explore link relationships