Brain Grain Quiz Coach — Alexa+ MCP Server

A self-hosted MCP server that turns Alexa+ (or any MCP client) into a bilingual Tamil / English exam coach.

"Alexa, quiz me on Indian Polity."

Built for the Build, Ship, Shape: Amazon Developer Hackathon 2026, Alexa+ track. Content comes from Brain Grain, a live exam-prep product used by learners in Tamil Nadu preparing for TNPSC, UPSC, CTET and school exams.

• MCP spec 2025-11-25 via @modelcontextprotocol/sdk 1.30.0

• Streamable HTTP transport (/mcp) and stdio

• Every question is a real previous-year / textbook question with a verified explanation — nothing is generated on the fly

• Wrong answer → the next question is a sibling on the same topic (adaptive follow-up)

Tools

Related MCP server: Ace Achievers MCP Server

Run it

npm install
npm start            # Streamable HTTP on http://localhost:3333/mcp
npm run stdio        # stdio transport for Claude Desktop / Cursor / MCP Inspector
npm test

Try it in the MCP Inspector:

npx @modelcontextprotocol/inspector node src/stdio.js

Claude Desktop config:

{ "mcpServers": { "braingrain": { "command": "node", "args": ["C:/path/to/braingrain-alexa-mcp/src/stdio.js"] } } }

Content

By default the server reads Brain Grain's live app-packs — public, read-only JSON at https://braingrain.in/data/app-packs/<exam>/<subject>.json. Exams: tnpsc-group1, tnpsc-group2, tnpsc-group4 (alias tnpsc), ctet, tntet. Subjects for TNPSC: polity, history, geography, economy, science, current, aptitude. Every pack is bilingual (q/q2, o/o2, e/e2).

data/sample-bank.json ships 65 bilingual TNPSC Polity questions (5 per topic across 13 topics) as a fallback: set BRAINGRAIN_OFFLINE=1 to force it, and it kicks in automatically if the network is down.

Alexa+

Register the hosted /mcp endpoint as an Alexa+ MCP integration. Session identity: pass the Alexa user/profile id as learner so streaks persist across turns.

Repo layout

src/server.js   Streamable HTTP entry (express)
src/stdio.js    stdio entry
src/tools.js    the five tools
src/bank.js     sample-bank / API adapter
src/session.js  per-learner state + adaptive queue
data/           sample bank
friction-log.md what got in the way while building (hackathon friction log)

Licence

MIT — see LICENSE. Sample content © Brain Grain, included for evaluation.

Demo

npm start then open http://localhost:3333/demo/ — a simulated Alexa+ screen that drives the real server over MCP, with the JSON-RPC frames shown alongside. node demo/record.mjs records it to demo/out/demo.webm (needs Playwright; set PLAYWRIGHT_FROM to a project that has it).