Tend — Voice-First Family Care Circle for Alexa+

Amazon Developer Hackathon (Build, Ship, Shape)
Primary Track: Alexa+
Mini Challenges: AWS Builder & Open Source

Tend is an ambient, voice-first family care circle living inside Alexa+, engineered specifically for families supporting an aging parent. Without requiring parents to adopt complex smartphone apps, Tend empowers elders to log routines ("Alexa, tell Tend I took my morning pills") and allows adult children to stay informed ("Alexa, how's Mom doing today?").

Key Highlights

• Alexa+ Native MCP Implementation: Exposes 8 focused voice tools conforming to the official Model Context Protocol (spec 2025-11-25).

• Sub-500ms Latency ($p95 < 250\text{ ms}$): Zero LLM calls in the synchronous voice request path. Spoken briefings are built deterministically from $\le 4$ DynamoDB queries.

• Enterprise-Grade Auth & Security: Full OAuth 2.1 authorization code flow with PKCE S256, RFC 9728 Protected Resource Metadata (PRM), and bare 401 Unauthorized unauthenticated responses.

• Interactive Multimodal Care Board: Supports Alexa screen devices via the MCP App specification (ui://tend/care-board) styled according to DESIGN.md.

• Asynchronous Intelligence (AWS Builder): Scheduled EventBridge triggers an async Lambda digest worker utilizing Amazon Bedrock (Converse API) to summarize longitudinal trends into pre-cached insights.

• Open Source Conformance Tool: Includes alexa-mcp-check (packages/conformance), an Apache-2.0 automated test suite that validates any MCP server against Alexa+ protocol, auth, and voice linter standards.

Related MCP server: KinKeep

Codebase Architecture & MCP SDK References

As required by the Alexa+ hackathon criteria, the official @modelcontextprotocol/sdk is directly integrated and utilized:

• Official MCP SDK Server Import: apps/mcp-server/src/server.ts
import { McpServer } from "@modelcontextprotocol/sdk/server/mcp.js";

• Streamable HTTP Stateless Transport: apps/mcp-server/src/index.ts
import { WebStandardStreamableHTTPServerTransport } from "@modelcontextprotocol/sdk/server/webStandardStreamableHttp.js";

• Server Initialization & Capabilities: apps/mcp-server/src/server.ts
  Initializes McpServer declaring tools and resources capabilities for specification version 2025-11-25.

• Tool Registrations: apps/mcp-server/src/server.ts
  Registers all 8 voice tools with Zod input schemas and spoken response envelopes.

• MCP App Multimodal Resource: apps/mcp-server/src/server.ts
  Registers ui://tend/care-board resource rendering interactive care board HTML.

• OAuth 2.1 & RFC 9728 Handlers: apps/mcp-server/src/oauth.ts

• Core Domain & Repositories: packages/core/src/index.ts

• Open Source Conformance CLI: packages/conformance/src/cli.ts

• AWS CDK v2 Infrastructure: infra/cdk/src/index.ts

• Care Console UI Application: apps/console/src/index.ts

Monorepo Setup & Quickstart

Tend uses pnpm workspaces (Node 22+ recommended):

# 1. Install dependencies across all packages
pnpm install

# 2. Run complete verification gate (typecheck + lint + test + conformance)
pnpm verify

# 3. Start Tend MCP Server & Echo Show Care Board (Terminal 1)
pnpm --filter @tend/mcp-server start
# -> Listening at http://localhost:3000
# -> Live Care Board: http://localhost:3000/board
# -> Streamable HTTP: http://localhost:3000/mcp

# 4. Start Tend Care Console UI (Terminal 2)
pnpm --filter @tend/console start
# -> Running at http://localhost:3001

License

Tend is open-source software licensed under the Apache License, Version 2.0.