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Lab 2 Extending the MCP Service

Estimated time to read: 3 minutes

What You'll Learn

In this lab, you will:

  • Enable the MCP time service in the MCP server
  • Understand how to register new tools using the @mcp.tool() decorator
  • Configure the agent to handle time-related queries
  • Use natural language to ask time-based questions about sales data
  • Explore how the LLM uses current time context to interpret relative date queries

Introduction

In this lab, we will extend the MCP server to include a time service. This service will allow us to retrieve the current time for use in our Sales Assistant application. For example, the LLM can use the services to determine the current time and respond to user queries that are time related, such as "what were the sales last week?" or "what were last quarters sales?".

The time service will be implemented as a new tool in the MCP server, which can be called by the LLM to get the current time.

Lab Exercise

Enable the MCP time service by uncommenting the get_current_utc_date function in the mcp_server_sales_analysis.py file. This function will return the current UTC date and time in ISO format, which can be used by the LLM to answer time-related queries.

  1. Open the mcp_server_sales_analysis.py file in the src/python/mcp_server directory.

  2. Uncomment the @mcp.tool() decorator for the get_current_utc_date function. This decorator registers the function as an MCP tool that can be called by the LLM. After uncommenting, your code should look like this:

    @mcp.tool()
async def get_current_utc_date() -> str:
    """Get the current UTC date and time in ISO format.

    Returns the current date and time in UTC timezone, useful for date-based queries,
    filtering recent data, or understanding the current context for time-sensitive analysis.

    Returns:
        Current UTC date and time in ISO format (YYYY-MM-DDTHH:MM:SS.fffffZ)
    """
    try:
        current_utc = datetime.now(timezone.utc)
        return f"Current UTC Date/Time: {current_utc.isoformat()}"
    except Exception as e:
        return f"Error retrieving current UTC date: {e!s}"

  3. Review the function's docstring to understand its purpose and how it can be used.

  4. Save the change to the file

tbd

Run the Agent App

  1. Press F5 to run the app.
  2. Select Preview in Editor to open the agent app in a new editor tab.

Start a Conversation with the Agent

Copy and paste the following prompt into the agent app to start a conversation:

what were the sales last week?