"""Test that parameter descriptions are properly exposed through list_tools"""
import pytest
from pydantic import Field
from mcp.server.fastmcp import FastMCP
@pytest.mark.asyncio
async def test_parameter_descriptions():
mcp = FastMCP("Test Server")
@mcp.tool()
def greet(
name: str = Field(description="The name to greet"),
title: str = Field(description="Optional title", default=""),
) -> str:
"""A greeting tool"""
return f"Hello {title} {name}"
tools = await mcp.list_tools()
assert len(tools) == 1
tool = tools[0]
# Check that parameter descriptions are present in the schema
properties = tool.inputSchema["properties"]
assert "name" in properties
assert properties["name"]["description"] == "The name to greet"
assert "title" in properties
assert properties["title"]["description"] == "Optional title"