from pydantic import BaseModel, Field
from datetime import datetime
from typing import List, Any

class AgentStep(BaseModel):
    agent_name: str
    input: Any
    output: Any
    duration_ms: int
    timestamp: datetime = Field(default_factory=datetime.utcnow)

class Trace(BaseModel):
    trace_id: str
    workplan_id: str
    signal_id: str
    agents: List[AgentStep] = []
    total_duration_ms: int = 0
    created_at: datetime = Field(default_factory=datetime.utcnow)