D&D MCP Server

Instructions

Implementation Reference

• src/gamemaster_mcp/main.py:433-455 (handler)

  The handler function for the 'create_location' tool. It is registered via the @mcp.tool decorator. Validates input using Annotated Fields, creates a Location model instance, persists it via storage.add_location, and returns a confirmation message.

  @mcp.tool
  def create_location(
      name: Annotated[str, Field(description="Location name")],
      location_type: Annotated[str, Field(description="Type of location (city, town, village, dungeon, etc.)")],
      description: Annotated[str, Field(description="Location description")],
      population: Annotated[int | None, Field(description="Population (if applicable)", ge=0)] = None,
      government: Annotated[str | None, Field(description="Government type")] = None,
      notable_features: Annotated[list[str] | None, Field(description="Notable features")] = None,
      notes: Annotated[str, Field(description="Additional notes")] = "",
  ) -> str:
      """Create a new location."""
      location = Location(
          name=name,
          location_type=location_type,
          description=description,
          population=population,
          government=government,
          notable_features=notable_features or [],
          notes=notes
      )
  
      storage.add_location(location)
      return f"Created location '{location.name}' ({location.location_type})"

• src/gamemaster_mcp/models.py:289-301 (schema)

  Pydantic BaseModel defining the schema for Location objects created by the 'create_location' tool.

  class Location(BaseModel):
      """Geographic location or settlement."""
      id: str = Field(default_factory=lambda: random(length=8))
      name: str
      location_type: str  # city, town, village, dungeon, forest, etc.
      description: str
      population: int | None = None
      government: str | None = None
      notable_features: list[str] = Field(default_factory=list)
      npcs: list[str] = Field(default_factory=list)  # NPC names
      connections: list[str] = Field(default_factory=list)  # Connected locations
      notes: str = ""