"""Elicitation utilities for MCP server."""
from fastmcp import Context
from mcp_server.models.itinerary_models import ItineraryPreferences
async def elicit_trip_extension(
ctx: Context,
start_date: str,
current_days: int,
min_days: int = 2
) -> tuple[int, str]:
"""
Elicit user preference to extend trip if below minimum days.
This function handles the elicitation flow for suggesting minimum trip duration.
It will:
1. Check if current days is below minimum
2. Prompt user to extend the trip if supported by client
3. Handle cases where elicitation is not supported
4. Return updated days and optional warning note
Args:
ctx: MCP Context for elicitation
start_date: Trip start date as string
current_days: Current number of days for the trip
min_days: Minimum recommended days (default: 2)
Returns:
tuple: (updated_days, elicitation_note)
- updated_days: The number of days after elicitation (extended or original)
- elicitation_note: Empty string or warning message if elicitation not supported
Raises:
ValueError: If user cancels the trip extension
"""
elicitation_note = ""
days = current_days
# Only elicit if current days is below minimum
if current_days < min_days:
try:
await ctx.info(f"Elicitation: Suggest minimum {min_days} days for a better itinerary")
result = await ctx.elicit(
message=(
f"Only {current_days} day(s) detected for your itinerary starting on {start_date}! "
f"For a meaningful travel experience, we recommend at least {min_days} days. "
"This allows for varied activities, proper rest, and a better exploration of the destination. "
f"Would you like to extend your trip to {min_days} or more days?"
),
response_type=ItineraryPreferences,
)
if result.action == "accept" and result.data:
if result.data.extendTrip:
# Use the new extended days
days = max(result.data.newDays, min_days) # Ensure at least min_days
await ctx.info(f"Trip extended to {days} days")
else:
raise ValueError(
f"[CANCELLED] Itinerary generation cancelled. "
f"Please plan for at least {min_days} days for a better experience."
)
else:
raise ValueError("[CANCELLED] Itinerary generation cancelled by user.")
except (AttributeError, NotImplementedError, Exception) as e:
# If it's a ValueError (user cancellation), re-raise it
if isinstance(e, ValueError):
raise
# If elicitation is not supported by the client, continue with current days
# but add a warning message to the output
await ctx.error(
f"Note: Elicitation not supported by client ({type(e).__name__}). "
f"Proceeding with {current_days}-day itinerary."
)
elicitation_note = (
f"NOTE: Your MCP client does not support interactive elicitation. "
f"We recommend at least {min_days} days for a better travel experience. "
f"Proceeding with {current_days}-day itinerary.\n\n"
)
return days, elicitation_note
