User Elicitation
62%
Implementing Elicitation
To put in work the elicitation system, we are going to add the necessary code that will do the following:
- Perform a fuzzy search for the breed name provided by the user.
- Return the best match depending on the similarity score.
- If the fuzzy search returns a close match, we will proceed with the elicitation.
We're going to use get_close_matches from the difflib standard library module to perform the fuzzy search. This function takes a query string and a list of possible matches, and returns the closest matches based on string similarity.
Example:
from difflib import get_close_matches
[...]
BREED_MULTIPLIERS = {
"labrador": 7,
"chihuahua": 5,
"german shepherd": 8,
"bulldog": 6,
}
def get_breed_multiplier(breed: str) -> int | None:
"""Fetch the age multiplier for a given dog breed."""
return BREED_MULTIPLIERS.get(breed.lower())
@mcp.tool
async def dog_to_human_age(
age: Annotated[int, Field(ge=0, le=30, description="The dog's age in years")],
breed: Annotated[str, Field(description="The dog's breed")],
ctx: Context,
) -> int:
"""Calculate the real age of a dog in human years based on its breed."""
# Let the client know what we're doing
await ctx.info(f"Looking up breed multiplier for '{breed}'")
multiplier = get_breed_multiplier(breed)
if multiplier is None:
# Look for 1 similar breed name
suggestions = get_close_matches(
breed.lower(), BREED_MULTIPLIERS.keys(), n=1, cutoff=0.6
)
if suggestions:
# Elicit the user with the best match
[...]
Here is the full code that implements elicitation:
cat > $HOME/workspace/puppy_guide/server/main.py << EOF
import os
from difflib import get_close_matches
from typing import Annotated
from dotenv import load_dotenv
from pydantic import Field
from fastmcp import Context
from fastmcp import FastMCP
from fastmcp.exceptions import ToolError
load_dotenv()
mcp = FastMCP(
name=os.getenv("MCP_NAME"),
instructions=os.getenv("MCP_INSTRUCTIONS"),
)
BREED_MULTIPLIERS = {
"labrador": 7,
"chihuahua": 5,
"german shepherd": 8,
"bulldog": 6,
}
def get_breed_multiplier(breed: str) -> int | None:
"""Fetch the age multiplier for a given dog breed."""
return BREED_MULTIPLIERS.get(breed.lower())
@mcp.tool
async def dog_to_human_age(
age: Annotated[int, Field(ge=0, le=30, description="The dog's age in years")],
breed: Annotated[str, Field(description="The dog's breed")],
ctx: Context,
) -> int:
"""Calculate the real age of a dog in human years based on its breed."""
# Let the client know what we're doing
await ctx.info(f"Looking up breed multiplier for '{breed}Practical MCP with FastMCP & LangChain
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