Hayday Server

Live HayDay game data — crops, products, animals, machines, and level unlocks — served as MCP tools for any AI agent.

Works with opencode, Claude Desktop, Cursor, VS Code, and any MCP-compatible client.

Not a bot. Not an auto-player. This is a read-only data lookup tool. It does not interact with the HayDay game, does not send inputs, does not automate gameplay, and cannot be used to play on your behalf. It only answers questions about game mechanics — like a wiki you can query from your AI.

Why?

HayDay is a deep game with hundreds of items, recipes, and levels. Keeping track of what to plant, what to craft, and what unlocks next is tedious. This MCP server gives your AI assistant the full game data so it can help you plan your farm — not play it for you.

How It Works

AI agent → MCP protocol → HayDay Data MCP → hayday.info API (live) → structured data
                                    ↓
                           1-hour in-memory cache

Data is fetched live from hayday.info on every tool call, with a 1-hour cache to avoid rate limits. When Supercell updates the game, your AI sees the new data automatically — no manual updates needed.

Quick Start

git clone https://github.com/Mohib1992/hayday-mcp-server.git
cd hayday-mcp-server
npm install
node server.js

The server starts and listens for MCP connections via stdio. Nothing happens until an AI client connects.

Tools

Tool	Description	Example
search_items	Search items by name or machine	"wheat", "bakery", "cheese"
get_item	Full details for a specific product	"Bread"
get_machines	List all 48 machine/category names	—
get_by_machine	All products from a machine	"Dairy", "Bakery", "Crops"
get_crops	All field crops + trees/bushes	—
get_animals	All animal products (eggs, milk, etc.)	—
get_level_unlocks	What unlocks at a specific level	level: 30
get_unlocks_upto	Everything available up to a level	level: 20
get_best_profit	Top items by profit/hour	limit: 10, minLevel: 1
compare_profit	Compare profit/time for specific items	["Wheat", "Corn", "Bread"]
clear_cache	Force refresh from live source	—

Example Queries

"What's the most profitable crop at level 15?"

→ Call get_best_profit(minLevel: 1, limit: 5) and filter by machine: "Crops".

"Compare bread vs corn bread"

→ Call compare_profit(products: ["Bread", "Corn bread"]).

"What do I unlock at level 30?"

→ Call get_level_unlocks(level: 30).

Client Setup

opencode

Add to opencode.jsonc in your project root:

{
  "mcpServers": {
    "hayday-data": {
      "command": "node",
      "args": ["server.js"],
      "cwd": "/path/to/hayday-data-mcp"
    }
  }
}

Claude Desktop

Add to claude_desktop_config.json:

{
  "mcpServers": {
    "hayday-data": {
      "command": "node",
      "args": ["server.js"],
      "cwd": "/path/to/hayday-data-mcp"
    }
  }
}

Cursor

Settings → Features → MCP → Add new server:

Field	Value
Name	hayday-data
Type	command
Command	node /path/to/hayday-data-mcp/server.js

VS Code (Continue.dev)

Add to ~/.continue/config.json:

{
  "experimental": {
    "mcpServers": {
      "hayday-data": {
        "command": "node",
        "args": ["server.js"],
        "cwd": "/path/to/hayday-data-mcp"
      }
    }
  }
}

Data Source

All data comes from hayday.info — a community-run HayDay database. The /api/production-data endpoint returns 348 items across 48 categories. Data is cached in memory for 1 hour.

What's included:

• Field crops + trees & bushes
• Animal products (eggs, milk, bacon, wool, etc.)
• All machine-made products (Bakery, Dairy, BBQ Grill, etc.)
• Level unlock information
• Profit/hour calculations (provided by source)
• XP and XP/hour

What's not included:

• Ingredient/recipe details (which items combine to make a product)
• Building upgrade costs
• Derby / boat / town data

Architecture

hayday-mcp-server/
  server.js            # MCP server (JSON-RPC over stdio, zero framework deps)
  lib/
    hayday.js          # Fetches & indexes live data from hayday.info
    cache.js           # 1-hour TTL cache
  test/
    api.test.js        # API layer smoke tests
    mcp.test.js        # MCP protocol smoke tests
  package.json
  CHANGELOG.md
  LICENSE              # MIT

Troubleshooting

Problem	Likely Cause	Fix
Server starts but tools return nothing	Client not connected to server	Check MCP config path in your client settings
"API returned 429" or slow responses	Rate limited by hayday.info	Wait 1 hour (cache auto-cools down), or call clear_cache
"Product not found" for a known item	Case mismatch or item name changed	Use search_items first to find exact name
"Machine not found"	Name mismatch	Use get_machines to get exact machine names
Server crashes after stdin closes	Expected behavior (stdio transport ended)	Just restart the server
Data seems outdated	Cache hit (1hr TTL)	Call clear_cache to force a live fetch

Testing

npm test

Runs 20+ smoke tests covering the API layer and MCP protocol using Node.js built-in node:test.

Contributing

1. Fork the repo
2. Create a feature branch
3. Run npm test to verify
4. Open a pull request

License

MIT

---

Legal notice

This project is an independent data tool and is not affiliated with, endorsed by, or connected to Supercell Oy. HayDay is a trademark of Supercell Oy. All game data is sourced from publicly available community resources. This tool is read-only and does not interact with the HayDay game client, its servers, or its APIs. It is designed for informational and educational purposes only.