"""Transport-agnostic error types raised by the core.

Core tool handlers and the authorization layer must not depend on the web stack
(FastAPI). They raise :class:`ToolError` carrying an advisory HTTP status code;
each transport adapter maps it to its own wire format (the HTTP adapter to
``fastapi.HTTPException``, the stdio adapter to an MCP error). This keeps the
core importable without FastAPI installed.
"""

from __future__ import annotations


class ToolError(Exception):
    """Error raised by a core tool handler or the authorization layer.

    Args:
        message: Human-readable, non-sensitive error detail.
        status_code: Advisory HTTP status (e.g. 403 for denied). Adapters map
            this to their transport; the stdio adapter only uses the message.
    """

    def __init__(self, message: str, *, status_code: int = 400) -> None:
        super().__init__(message)
        self.status_code = status_code
        self.detail = message