from typing import Annotated

from pydantic import BaseModel

from mcp.server import MCPServer

from mcp.server.mcpserver import Resolve

mcp = MCPServer("Bookshop")

INVENTORY = {"Dune": 7, "Neuromancer": 0}

class Stock(BaseModel):

title: str

copies: int

async def check_stock(title: str) -> Stock:

return Stock(title=title, copies=INVENTORY.get(title, 0))

async def estimate_delivery(stock: Annotated[Stock, Resolve(check_stock)]) -> str:

return "tomorrow" if stock.copies > 0 else "in 2-3 weeks"

@mcp.tool()

async def order_book(

title: str,

stock: Annotated[Stock, Resolve(check_stock)],

delivery: Annotated[str, Resolve(estimate_delivery)],

) -> str:

"""Order a book from the shop."""

if stock.copies == 0:

return f"{title!r} is on backorder; it would arrive {delivery}."

return f"Ordered {title!r}; it arrives {delivery}."