"""
Agent error protocol.

Structured exceptions raised by expert agents (e.g. The Librarian) so
callers - the delegation wrappers in src/agents/delegation.py - can
report success=False and map failures to curated user-safe messages
while exception detail stays in the logs.
"""


class AgentError(Exception):
    """Base exception for agent errors."""

    def __init__(self, message: str, agent_name: str = "unknown"):
        self.message = message
        self.agent_name = agent_name
        super().__init__(f"[{agent_name}] {message}")