fix: main.py — Создайть просто AI агент на Python с применением langchain

This commit is contained in:
2026-07-02 07:11:58 +00:00
parent 8f03c134e4
commit 2fbfb5858f
+63 -75
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@@ -1,18 +1,18 @@
import os
import asyncio
from typing import List, Dict, Any
from typing import Any, Dict, List
from pydantic import SecretStr
from langchain_openai import ChatOpenAI
from langchain_core.messages import HumanMessage, BaseMessage
from langchain_core.messages import HumanMessage, AIMessage, ToolMessage
from langchain.tools import tool
from deepagents import create_deep_agent
from deepagents.backends import FilesystemBackend, LocalShellBackend, CompositeBackend
from deepagents.backends import CompositeBackend, LocalShellBackend, FilesystemBackend
# ----------------------------------------------------------------------
# Configuration
# ----------------------------------------------------------------------
# LLM - OpenRouter (free tier). The API key must be stored in the environment.
# DESIGN DECISION: Use OpenRouter LLM as required by the technical constraints.
# NECESSITY: The course forbids local LM endpoints and mandates OpenRouter for all LLM calls.
# OPTIMALITY: Guarantees consistent API compatibility with OpenAI SDK and avoids GPU requirements.
# ALTERNATIVES CONSIDERED: Local LM via http://localhost:1234 - rejected due to explicit prohibition.
llm = ChatOpenAI(
model="openai/gpt-oss-20b:free",
base_url="https://openrouter.ai/api/v1",
@@ -20,8 +20,7 @@ llm = ChatOpenAI(
temperature=0.7,
)
# Backend for the agents - a simple composite that allows file operations
# and execution of shell commands inside a sandboxed workspace.
# Backend required by deepagents - combines a shell and filesystem workspace.
backend = CompositeBackend(
[
LocalShellBackend(workspace_dir="./workspace"),
@@ -29,91 +28,80 @@ backend = CompositeBackend(
]
)
# ----------------------------------------------------------------------
# Sub-agent: price generator
# ----------------------------------------------------------------------
def _create_price_subagent() -> Any:
"""
Creates a lightweight sub-agent that, given a product and a city,
returns a markdown table with a plausible price and a store name.
The sub-agent re-uses the same LLM and backend as the main agent.
"""
subagent = create_deep_agent(
model=llm,
tools=[], # No additional tools are required for price generation
backend=backend,
system_prompt=(
"You are a price-estimation sub-agent. "
"Given a product name and a city, generate a realistic price "
"in Russian rubles and suggest a typical store. "
"Return the result as a markdown table with columns: "
"`Продукт`, `Цена (руб.)`, `Магазин`."
),
)
return subagent
_price_subagent = _create_price_subagent()
@tool
def get_price(product: str, city: str) -> str:
"""
Estimate the price of a product in a given city.
The function creates a sub-agent that returns a markdown table:
Получить примерную цену продукта в указанном городе.
Возвращает таблицу в markdown-формате:
| Продукт | Цена (руб.) | Магазин |
"""
# Build the prompt for the sub-agent
prompt = HumanMessage(
content=f"Продукт: {product}\nГород: {city}\nСгенерируй цену."
# DESIGN DECISION: Sub-agent is created inside the tool using the same LLM.
# NECESSITY: The assignment explicitly requires a hierarchical agent where a tool
# invokes its own agent to generate realistic prices.
# OPTIMALITY: Re-using the same LLM and backend keeps the environment consistent
# and avoids additional dependencies.
# ALTERNATIVES CONSIDERED: Calling an external API for prices - rejected because
# it would break the self-contained requirement.
sub_agent = create_deep_agent(
model=llm,
tools=[], # No further tools needed for price generation
backend=backend,
system_prompt=(
"Ты суб-агент, который генерирует реалистичную цену продукта в заданном городе. "
"Ответ дай в виде markdown-таблицы с колонками: Продукт, Цена (руб.), Магазин."
),
)
# Invoke the sub-agent asynchronously and wait for the result
result = asyncio.run(
_price_subagent.ainvoke(
{"messages": [prompt]},
# Формируем запрос к суб-агенту
query = f"Сгенерируй цену для продукта '{product}' в городе '{city}'."
# Асинхронный вызов суб-агента
async def invoke_sub() -> Dict[str, Any]:
return await sub_agent.ainvoke(
{"messages": [HumanMessage(content=query)]},
{"configurable": {"thread_id": f"price-{product}-{city}"}},
)
)
# The sub-agent returns a list of messages; the last one contains the table
final_message = result["messages"][-1]
return final_message.content if isinstance(final_message, BaseMessage) else str(final_message)
# ----------------------------------------------------------------------
# Main agent: shopping list planner
# ----------------------------------------------------------------------
main_agent = create_deep_agent(
# Запускаем цикл событий, если уже внутри async контекста
try:
loop = asyncio.get_running_loop()
result = loop.create_task(invoke_sub())
sub_result = asyncio.run(invoke_sub())
except RuntimeError:
# No running loop - create one
sub_result = asyncio.run(invoke_sub())
# Последнее сообщение суб-агента содержит таблицу
price_table = sub_result["messages"][-1].content
return price_table
# Главный агент
agent = create_deep_agent(
model=llm,
tools=[get_price],
backend=backend,
system_prompt="Ты помощник по планированию покупок.",
)
def format_message(msg: BaseMessage) -> str:
"""
Convert a LangChain message to a readable string.
Handles normal text messages and tool calls.
"""
if hasattr(msg, "content") and msg.content:
return msg.content
# Tool call representation
if hasattr(msg, "tool_calls") and msg.tool_calls:
call = msg.tool_calls[0]
name = call["name"]
args = ", ".join(f"{k}={v!r}" for k, v in call["args"].items())
return f"{name}({args})"
def format_message(msg: Any) -> str:
"""Привести сообщение к читаемому виду."""
if isinstance(msg, AIMessage) or isinstance(msg, HumanMessage):
return f"{msg.type.upper()}: {msg.content}"
if isinstance(msg, ToolMessage):
return f"TOOL CALL: {msg.name}({msg.args}) -> {msg.content}"
# Fallback
return str(msg)
async def main() -> None:
user_query = (
"Помоги составить список покупок: молоко, хлеб, яблоки. "
"Я нахожусь в Казани."
)
result = await main_agent.ainvoke(
user_query = "Помоги составить список покупок: молоко, хлеб, яблоки. Я нахожусь в Казани."
result = await agent.ainvoke(
{"messages": [HumanMessage(content=user_query)]},
{"configurable": {"thread_id": "shopping-session-1"}},
{"configurable": {"thread_id": "session-1"}},
)
# Print the whole conversation chain
for i, msg in enumerate(result["messages"], start=1):
print(f"--- Message {i} ---")
print(format_message(msg))
# Вывод всей цепочки сообщений
for i, message in enumerate(result["messages"]):
print(f"--- Message {i + 1} ---")
print(format_message(message))
print()
if __name__ == "__main__":