| Filename | Latest commit message | Latest commit date |
|---|---|---|
* build app-with-deps
* make registerAppTool more interchangeable w/ server.registerTool
* feat: use structuredContent in all example servers
All servers now return structuredContent alongside JSON text content.
All mcp-apps now read structuredContent directly (no JSON.parse fallback).
Updated servers:
- basic-server-vanillajs
- budget-allocator-server
- cohort-heatmap-server
- customer-segmentation-server
- integration-server
- scenario-modeler-server
- system-monitor-server
- threejs-server
- video-resource-server
- wiki-explorer-server
* feat: add outputSchema to all example servers
Define output schemas for structuredContent validation:
- basic-server-vanillajs: { time: string }
- budget-allocator-server: BudgetDataResponseSchema
- cohort-heatmap-server: CohortDataSchema
- customer-segmentation-server: customers/segments schema
- integration-server: { time: string }
- scenario-modeler-server: templates/defaultInputs schema
- system-monitor-server: SystemStatsSchema
- threejs-server: { code, height }
- video-resource-server: { videoUri, description }
- wiki-explorer-server: { page, links, error }
* prettier:fix
* make registerAppTool more interchangeable w/ server.registerTool
* feat: use structuredContent in all example servers
All servers now return structuredContent alongside JSON text content.
All mcp-apps now read structuredContent directly (no JSON.parse fallback).
Updated servers:
- basic-server-vanillajs
- budget-allocator-server
- cohort-heatmap-server
- customer-segmentation-server
- integration-server
- scenario-modeler-server
- system-monitor-server
- threejs-server
- video-resource-server
- wiki-explorer-server
* feat: add outputSchema to all example servers
Define output schemas for structuredContent validation:
- basic-server-vanillajs: { time: string }
- budget-allocator-server: BudgetDataResponseSchema
- cohort-heatmap-server: CohortDataSchema
- customer-segmentation-server: customers/segments schema
- integration-server: { time: string }
- scenario-modeler-server: templates/defaultInputs schema
- system-monitor-server: SystemStatsSchema
- threejs-server: { code, height }
- video-resource-server: { videoUri, description }
- wiki-explorer-server: { page, links, error }
* prettier:fix
* revert: remove unrelated workflow, version, and arch changes
* chore: update package-lock.json
* refactor(basic-server-vanillajs): address PR review comments
- Simplify server.ts to return plain time string in text content (not JSON),
matching the quickstart guide pattern
- Add defensive coding in mcp-app.ts with optional chaining and fallback
to handle potential type mismatches gracefully
* refactor: restore rich text formatting for LLM-readable content
Restore the human-readable text formatting functions that were removed,
providing meaningful summaries in the text content while keeping
structuredContent for programmatic UI consumption:
- budget-allocator-server: formatBudgetSummary with config overview
- cohort-heatmap-server: formatCohortSummary with retention stats
- scenario-modeler-server: formatScenarioSummary with financial metrics
|
||
| .. | ||
| src | ||
| mcp-app.html | ||
| package.json | ||
| README.md | ||
| server-utils.ts | ||
| server.ts | ||
| tsconfig.json | ||
| vite.config.ts | ||
Example: Cohort Heatmap App
A demo MCP App that displays cohort retention data as an interactive heatmap, showing customer retention over time by signup month.
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Features
- Cohort Retention Heatmap: Color-coded grid showing retention percentages across cohorts and time periods
- Multiple Metrics: Switch between Retention %, Revenue Retention, and Active Users
- Period Types: View data by monthly or weekly intervals
- Interactive Exploration: Hover cells for detailed tooltips, click to highlight rows/columns
- Color Scale: Green (high retention) through yellow to red (low retention)
- 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-hostexample or another MCP Apps-compatible host.
Architecture
Server (server.ts)
Exposes a single get-cohort-data tool that returns:
- Cohort rows with signup month, original user count, and retention cells
- Period headers and labels
- Configurable parameters: metric type, period type, cohort count, max periods
The tool generates synthetic cohort data using an exponential decay model with configurable retention curves per metric type.
App (src/mcp-app.tsx)
- Uses React for the heatmap visualization
- Fetches data on mount and when filters change
- Displays retention percentages in a grid with HSL color interpolation
- Shows detailed tooltips on hover with user counts and exact retention values
- Supports row/column highlighting on cell click


