from mcp_types import ClientCapabilities, ElicitationCapability, RootsCapability, SamplingCapability

from pydantic import BaseModel

from mcp.server import MCPServer

from mcp.server.mcpserver import Context

mcp = MCPServer("Library")

class CardHolder(BaseModel):

name: str

@mcp.tool()

async def issue_card(ctx: Context) -> str:

"""Issue a new library card."""

answer = await ctx.elicit("What name should go on the card?", schema=CardHolder)

if answer.action == "accept":

return f"Card issued to {answer.data.name}."

return "No card issued."

@mcp.tool()

def client_features(ctx: Context) -> list[str]:

"""Which optional features the connected client declared."""

declared = {

"elicitation": ClientCapabilities(elicitation=ElicitationCapability()),

"sampling": ClientCapabilities(sampling=SamplingCapability()),

"roots": ClientCapabilities(roots=RootsCapability()),

}

return [name for name, capability in declared.items() if ctx.session.check_client_capability(capability)]