Tea Mixer AI Server

API service for AI-assisted Burmese milk tea recipe generation. It converts natural language preferences (sweetness level, astringency, milk texture) into exact milliliter ingredient formulations.

The repository provides two implementations:

1. worker/ (Recommended): Cloudflare Worker using Hono for edge deployment. This is the actively maintained version and includes the latest features, including Server-Sent Events (SSE) streaming.
2. server/ (Deprecated): Node.js/Express server for offline local development and traditional server environments.

FeaturesCopy Anchor Link

• Preference Parsing: Converts unstructured user taste requests into standardized volume ratios (tea, condensedMilk, evaporatedMilk, milk).
• SSE Streaming (Worker only): Real-time text and JSON response streaming via Server-Sent Events.
• Payload Validation: Strict request payload validation using Zod schemas.
• Provider Agnostic: Built on LangChain Core and OpenRouter to switch backend models via environment variables.

Tech StackCopy Anchor Link

• Runtimes: Cloudflare Workers (Primary), Node.js (>= 20)
• Frameworks: Hono, Express.js
• Model Orchestration: LangChain Core, LangChain OpenRouter
• Validation: Zod
• Tooling: TypeScript, pnpm, Wrangler, ESLint, Prettier

Setup & InstallationCopy Anchor Link

PrerequisitesCopy Anchor Link

• Node.js >= 20
• pnpm (npm install -g pnpm)
• OpenRouter API key

git clone https://github.com/nainghtetlinn/tea-suggestion.git
cd tea-suggestion

Option 1: Cloudflare Worker (Recommended)Copy Anchor Link

The Worker implementation is the primary version and includes streaming support.

cd worker
pnpm install

Configure your secrets:

pnpm wrangler secret put OPENROUTER_API_KEY
pnpm wrangler secret put OPENROUTER_MODEL # Optional

Run locally:

pnpm dev

The worker starts locally at http://127.0.0.1:8787.

Deploy to Cloudflare:

pnpm deploy

Option 2: Express Server (Deprecated)Copy Anchor Link

Used for offline development or running without Wrangler.

cd server
pnpm install

Create .env inside server/:

OPENROUTER_API_KEY=your_openrouter_api_key
PORT=3000

Start the development server:

pnpm dev

The server will listen at http://localhost:3000.

API ReferenceCopy Anchor Link

Cloudflare Worker (http://127.0.0.1:8787 or deployed URL)Copy Anchor Link

POST /chat-stream (Recommended)Copy Anchor Link

Streams the model's text response and ingredient payload in real time using Server-Sent Events.

Request:

curl -N -X POST "http://127.0.0.1:8787/chat-stream" \
  -H "Content-Type: application/json" \
  -d '{"preferences": "extra creamy, strong tea"}'

Response (200 OK): Returns a continuous text/event-stream.

POST /chatCopy Anchor Link

Non-streaming endpoint returning the final JSON payload.

Request:

curl -X POST "http://127.0.0.1:8787/chat" \
  -H "Content-Type: application/json" \
  -d '{"preferences": "less sweet and creamy"}'

Response (201 Created):

{
  "recipe": {
    "tea": 120,
    "condensedMilk": 20,
    "evaporatedMilk": 40,
    "milk": 0
  }
}

Express Server (http://localhost:3000) (Deprecated)Copy Anchor Link

POST /chatCopy Anchor Link

Accepts the same JSON payload as the worker's standard /chat route:

curl -X POST "http://localhost:3000/chat" \
  -H "Content-Type: application/json" \
  -d '{"preferences": "less sweet and creamy"}'

Project StructureCopy Anchor Link

tea-suggestion/
├── worker/                 # Cloudflare Worker deployment (Recommended)
│   └── src/
│       ├── schemas/        # Zod validation schemas
│       ├── services/       # Worker AI streaming logic
│       └── index.ts        # Hono entrypoint
├── server/                 # Express development server (Deprecated)
│   └── src/
│       ├── config/         # Environment variables & constants
│       ├── controllers/    # Route controllers
│       ├── middlewares/    # Error handling & validation
│       ├── routes/         # Express router definitions
│       ├── schemas/        # Zod validation schemas
│       └── services/       # LangChain service
├── test.http               # REST client test requests
└── README.md

ContributingCopy Anchor Link

This project is currently private and not accepting external contributions.

LicenseCopy Anchor Link

Copyright (c) 2026 Naing Htet Linn. All rights reserved.

This project and its source code are proprietary. Unauthorized copying, modification, distribution, or use of this software, in whole or in part, via any medium, is strictly prohibited without prior written permission from the author.