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Please reload this page . modelcontextprotocol / ext-apps Public * Notifications You must be signed in to change notification settings * Fork 377 * Star 2.8k * Code * Issues 124 * Pull requests 82 * Discussions * Actions * Projects * Security and quality 0 * Insights Additional navigation options * Code * Issues * Pull requests * Discussions * Actions * Projects * Security and quality * Insights Files Expand file tree main Breadcrumbs * ext-apps * / examples / scenario-modeler-server / Copy path Directory actions More options More options Directory actions More options More options Latest commit   History History History main Breadcrumbs * ext-apps * / examples / scenario-modeler-server / Copy path Top Folders and files Name Name Last commit message Last commit date parent directory .. src src     .gitignore .gitignore     README.md README.md     grid-cell.png grid-cell.png     main.ts main.ts     mcp-app.html mcp-app.html     package.json package.json     screenshot.png screenshot.png     server.ts server.ts     tsconfig.json tsconfig.json     tsconfig.server.json tsconfig.server.json     vite.config.ts vite.config.ts     View all files README.md Outline Example: SaaS Scenario Modeler A React-based demo MCP App that lets users adjust SaaS business parameters and see real-time 12-month projections of revenue, costs, and profitability with comparison against pre-built scenario templates. MCP Client Configuration Add to your MCP client configuration (stdio transport): { "mcpServers" : { "scenario-modeler" : { "command" : " npx " , "args" : [ " -y " , " --silent " , " --registry=https://registry.npmjs.org/ " , " @modelcontextprotocol/server-scenario-modeler " , " --stdio " ] } } } Local Development To test local modifications, use this configuration (replace ~/code/ext-apps with your clone path): { "mcpServers" : { "scenario-modeler" : { "command" : " bash " , "args" : [ " -c " , " cd ~/code/ext-apps/examples/scenario-modeler-server && npm run build >&2 && node dist/index.js --stdio " ] } } } Features * Interactive Parameters : 5 sliders for Starting MRR, Growth Rate, Churn Rate, Gross Margin, and Fixed Costs * 12-Month Projections : Line chart showing MRR, Gross Profit, and Net Profit over time * Scenario Templates : 5 pre-built business strategies (Bootstrapped, VC Rocketship, Cash Cow, Turnaround, Efficient Growth) * Template Comparison : Overlay dashed lines to compare your scenario against any template * Summary Metrics : Key metrics including Ending MRR, Total Revenue, Total Profit, and break-even month * Theme Support : Adapts to light/dark mode preferences Running * Install dependencies: npm install * Build and start the server: npm run start:http # for Streamable HTTP transport # OR npm run start:stdio # for stdio transport * View using the basic-host example or another MCP Apps-compatible host. Architecture Server ( server.ts ) Exposes a single get-scenario-data tool that returns: * 5 pre-built scenario templates with parameters, projections, and summaries * Default input values for the sliders * Optionally computes custom projections when customInputs are provided The tool is linked to a UI resource via _meta.ui.resourceUri . App ( src/ ) * Built with React for reactive slider updates and derived state management * Uses Chart.js for the line chart visualization * All projection calculations run client-side for instant slider feedback * Components: SliderRow , MetricCard , ProjectionChart * Template comparison shown as dashed overlay lines on the chart Footer (c) 2026 GitHub, Inc. Footer navigation * Terms * Privacy * Security * Status * Community * Docs * Contact * Manage cookies * Do not share my personal information You can’t perform that action at this time.