# -*- coding: utf-8 -*- """ 预定航班(范式) """ import asyncio import datetime from typing import AsyncGenerator from logfire_api.variables import ValueDoesNotEqual from pydantic import BaseModel, Field, field_validator from pydantic_ai import ( Agent, ApprovalRequired, DeferredToolRequests, DeferredToolResults, ModelMessage, ModelRetry, ModelSettings, RunContext, RunUsage, UsageLimits, ) from pydantic_ai.models.openai import OpenAIChatModel from pydantic_ai.providers.openai import OpenAIProvider from sqlalchemy.sql.dml import ReturningDelete DEEPSEEK_V4_FLASH_MODEL = OpenAIChatModel( model_name="deepseek-v4-flash", provider=OpenAIProvider( base_url="https://tokenhub.tencentmaas.com/v1", api_key="sk-D9Y1mCe8VlvNqLuSC4mAjqEwxJ2nW4C0h8a7EPn8kg9RLsHq", ), ) MODEL_SETTINGS = ModelSettings( temperature=0, extra_body={"thinking": {"type": "disabled"}} # 温度控制 ) # 禁用思考模式 class Deps(BaseModel): """ 依赖类 """ date: datetime.date = Field(..., description="日期") origin_airport_code: str = Field(..., description="出发机场代码") destination_airport_code: str = Field(..., description="到达机场代码") source_material: str = Field(..., description="来源资料") class Flight(BaseModel): """ 航班类 """ number: str = Field(..., description="航班号") date: datetime.date = Field(..., description="日期") origin_airport_code: str = Field(..., description="出发机场代码") destination_airport_code: str = Field(..., description="到达机场代码") airfare: int = Field(..., description="机票价格") @field_validator("origin_airport_code", "destination_airport_code") @classmethod def validate_airport_code(cls, airport_code: str) -> str: """校验机场代码""" if ( not airport_code.isalpha() or not airport_code.isupper() or len(airport_code) != 3 ): raise ValueError(f"机场代码须为英文、大写、3位字符串") return airport_code class FlightNoFound(BaseModel): """ 未查询到航班类 """ system_prompt = """你的任务是根据用户提供的日期、出发机场和到达机场选择航班。 1. 使用 extract_flights 从来源资料提取所有航班信息; 2. 使用 select_flight 从所有航班信息中选择匹配航班; """ # 主智能体 agent = Agent[Deps, Flight | FlightNoFound]( model=DEEPSEEK_V4_FLASH_MODEL, model_settings=MODEL_SETTINGS, deps_type=Deps, output_type=Flight | FlightNoFound, system_prompt=system_prompt, ) # 航班信息提取智能体 extraction_agent = Agent( model=DEEPSEEK_V4_FLASH_MODEL, model_settings=MODEL_SETTINGS, output_type=list[Flight], system_prompt=( "你的任务是根据给定的来源资料提取出所有航班信息,包括航班号、日期、出发机场代码、到达机场代码和机票价格。", "其中,出发机场代码和到达机场代码须为英文、大写、3位字符串,例如 San Francisco International Airport (SFO) 的机场代码为 SFO。", "若某航班信息不全则跳过该航班,若没有任何航班信息则返回空列表。", "禁止编造。", ), ) # 通过提示词约束输出 # 航班选择智能体 selection_agent = Agent( model=DEEPSEEK_V4_FLASH_MODEL, model_settings=MODEL_SETTINGS, output_type=Flight | FlightNoFound, system_prompt="你的任务是从所有航班信息中选择匹配用户提供的日期、出发机场和到达机场的航班:若有多个航班则选择最便宜的航班,选择完成需用户确认是否预定;若没有则返回 FlightNoFound。", ) """ 如何提高提取准确率 1. 系统提示词规则约束 2. 降低模型温度 3. 输出类型约定和输出模型校验 4. 业务规则约束(例如,输出不可为空列表) """ @agent.tool async def extract_flights(ctx: RunContext[Deps]) -> list[Flight]: """ 提取所有航班信息 """ result = await extraction_agent.run( ctx.deps.source_material, usage_limits=UsageLimits(request_limit=3), usage=ctx.usage, ) if len(output := result.output) != 8: raise ModelRetry("提取到的所有航班信息应为 8 条") return output @agent.tool async def select_flight(ctx: RunContext[Deps]) -> Flight | FlightNoFound: """ 选择航班 """ result = await selection_agent.run(ctx.deps.source_material, usage=ctx.usage) if isinstance(result.output, Flight): if not ctx.tool_call_approved: raise ApprovalRequired(metadata={"reason": "protected"}) return result.output @agent.output_validator async def validate_output( ctx: RunContext[Deps], output: Flight | FlightNoFound ) -> Flight | FlightNoFound: """ 输出校验 """ # 不校验未查询到航班 if isinstance(output, FlightNoFound): return output errors = [] if output.date != ctx.deps.date: errors.append(f"航班日期应为 {ctx.deps.date}, 不是 {output.date}") if output.origin != ctx.deps.origin: errors.append(f"航班出发机场应为 {ctx.deps.origin}, 不是 {output.origin}") if output.destination != ctx.deps.destination: errors.append( f"航班到达机场应为 {ctx.deps.destination}, 不是 {output.destination}" ) if errors: raise ModelRetry("\n".join(errors)) return output source_material = """ 1. Flight SFO-AK123 - Price: $350 - Origin: San Francisco International Airport (SFO) - Destination: Ted Stevens Anchorage International Airport (ANC) - Date: January 10, 2025 2. Flight SFO-AK456 - Price: $370 - Origin: San Francisco International Airport (SFO) - Destination: Fairbanks International Airport (FAI) - Date: January 10, 2025 3. Flight SFO-AK789 - Price: $400 - Origin: San Francisco International Airport (SFO) - Destination: Juneau International Airport (JNU) - Date: January 20, 2025 4. Flight NYC-LA101 - Price: $250 - Origin: San Francisco International Airport (SFO) - Destination: Ted Stevens Anchorage International Airport (ANC) - Date: January 10, 2025 5. Flight CHI-MIA202 - Price: $200 - Origin: Chicago O'Hare International Airport (ORD) - Destination: Miami International Airport (MIA) - Date: January 12, 2025 6. Flight BOS-SEA303 - Price: $120 - Origin: Boston Logan International Airport (BOS) - Destination: Ted Stevens Anchorage International Airport (ANC) - Date: January 12, 2025 7. Flight DFW-DEN404 - Price: $150 - Origin: Dallas/Fort Worth International Airport (DFW) - Destination: Denver International Airport (DEN) - Date: January 10, 2025 8. Flight ATL-HOU505 - Price: $180 - Origin: Hartsfield-Jackson Atlanta International Airport (ATL) - Destination: George Bush Intercontinental Airport (IAH) - Date: January 10, 2025 """ async def run_stream_events( user_prompt: str, deps: Deps, message_history: list[ModelMessage], usage: RunUsage, deferred_tool_results: DeferredToolResults | None = None, ) -> AsyncGenerator: async with agent.run_stream_events( user_prompt=user_prompt, deps=deps, message_history=message_history, usage=usage, deferred_tool_results=deferred_tool_results, ) as events: async for event in events: yield event async def main(): deps = Deps( source_material=source_material, date=datetime.date(2025, 1, 10), origin="SFO", destination="ANC", ) # message_history 传空列表,不要传 None msg_history: list[ModelMessage] = [] prompt = f"Find me a flight from {deps.origin} to {deps.destination} on {deps.date}" gen = run_stream_events( user_prompt=prompt, deps=deps, message_history=msg_history, usage=RunUsage(), ) # 消费异步生成器 async for ev in gen: print(ev) asyncio.run(main()) """ if not isinstance(event, AgentRunResultEvent): yield event else: result = event.result # 更新任务使用量 task.usage = usage_to_dict(result.usage) if isinstance(result.output, FlightDetail): content = "\n---\n已查询到航班,请回复 buy 购票 或 search 重新查询\n" # 更新任务节点为提取座位偏好 task.node = "seat_preference_extraction" else: content = ( "\n---\n未查询到满足您需求的航班,流程结束!\n" ) # 更新任务为空 task = None # 返回任务节点结果事件 yield TaskNodeResultEvent( task=task, content=content, ) yield event return # 提取座位偏好 case "seat_preference_extraction": if user_prompt == "buy": # 返回任务节点结果事件 yield TaskNodeResultEvent( task=task, content="请和我说下您的座位偏好:\nA、F 座位是靠窗位;1 排、14 排、20 排腿部空间更大、更舒展,你更想要靠窗座位,宽敞大空间座位", ) return elif user_prompt == "search": # 更新任务节点为航班查询 task.node = "flight_search" else: async with seat_preference_extraction_agent.run_stream_events( user_prompt=user_prompt, message_history=message_history, usage=usage_to_object(dict(task.usage)), usage_limits=usage_limits_to_object(dict(task.usage_limits)), ) as events: async for event in events: if not isinstance(event, AgentRunResultEvent): yield event else: result = event.result # 更新任务使用量 task.usage = usage_to_dict(result.usage) # 更新任务为空 task = None # 返回任务节点结果事件 yield TaskNodeResultEvent( task=task, content="已帮您定好座位,流程结束!", ) yield event return # 工具调用分片开始事件 case ToolCallPart( tool_name=tool_name, tool_call_id=tool_call_id ): # 构建消息实例 message = Message( type=MessageType.TOOL_CALL, title=tool_name, content=",", is_running=True, ) tool_call_ids.add(tool_call_id) # 添加至消息字典 dialog.thoughts[index] = Thought( type="tool_call", content="正在生成调用参数", ) # ========== 函数工具调用事件 ========== case FunctionToolCallEvent(tool_call_id=tool_call_id, part=part): # 获取分片索引 index = tool_call_ids[tool_call_id] match dialog.thoughts[index].type: # 工具检索 case "tool_search": dialog.thoughts[index].content = ( f"正在检索 {part.args_as_json_str()}" ) # 能力加载 case "capability_load": dialog.thoughts[index].content = ( f"正在加载能力 {part.tool_name}" ) # 工具调用 case "tool_call": dialog.thoughts[index].content = ( f"正在调用工具 {part.tool_name}" ) case _: continue # ========== 函数工具结果事件 ========== case FunctionToolResultEvent( tool_call_id=tool_call_id, content=content, ): index = tool_call_ids[tool_call_id] match dialog.thoughts[index].type: # 工具检索 case "tool_search": dialog.thoughts[index].content = ( content if isinstance(content, str) else "" ) # 暂仅考虑文本内容 # 能力加载 case "capability_load": dialog.thoughts[index].content = f"已加载 {content}" # 工具调用 case "tool_call": dialog.thoughts[index].content = f"已调用 {content}" case _: continue def init_work_flow() -> WorkFlow: return WorkFlow( type=WorkFlowType.BOOK_FLIGHT, deps=Dependences( source_material=source_material, date=datetime.date(2025, 1, 10), origin="SFO", destination="ANC", ), ) from application.states.models import ( WorkFlow, WorkFlowType, ) from application.workshop.models import ( DEEPSEEK_V4_FLASH_MODEL, MODEL_SETTINGS_DISABLED_THINKING, ) """