跳到主要内容

使用 Pytest/Vitest 和 LangSmith 测试 ReAct 代理

本教程将向您展示如何使用 LangSmith 与流行的测试工具 PytestVitest/Jest 的集成来评估您的 LLM 应用程序。我们将创建一个 ReAct 代理,该代理回答有关上市公司股票的问题,并为其编写全面的测试套件。

设置

本教程使用 LangGraph 进行代理编排,OpenAI 的 GPT-4oTavily 用于搜索,E2B 的 代码解释器,以及 Polygon 来检索股票数据,但可以通过少量修改将其适配于其他框架、模型和工具。Tavily、E2B 和 Polygon 都可以免费注册。

安装

首先,安装制作代理所需的软件包

pip install -U langgraph langchain[openai] langchain-community e2b-code-interpreter

接下来,安装测试框架

# Make sure you have langsmith>=0.3.1
pip install -U "langsmith[pytest]"

环境变量

设置以下环境变量

export LANGSMITH_TRACING=true
export LANGSMITH_API_KEY=<YOUR_LANGSMITH_API_KEY>

export OPENAI_API_KEY=<YOUR_OPENAI_API_KEY>
export TAVILY_API_KEY=<YOUR_TAVILY_API_KEY>
export E2B_API_KEY=<YOUR_E2B_API_KEY>
export POLYGON_API_KEY=<YOUR_POLYGON_API_KEY>

创建您的应用

要定义我们的 React 代理,我们将使用 LangGraph/LangGraph.js 进行编排,并使用 LangChain 用于 LLM 和工具。

定义工具

首先,我们将定义将在我们的代理中使用的工具。将有 3 个工具

  • 使用 Tavily 的搜索工具
  • 使用 E2B 的代码解释器工具
  • 使用 Polygon 的股票信息工具
from langchain_community.tools import TavilySearchResults
from e2b_code_interpreter import Sandbox
from langchain_community.tools.polygon.aggregates import PolygonAggregates
from langchain_community.utilities.polygon import PolygonAPIWrapper
from typing_extensions import Annotated, TypedDict, Optional, Literal

# Define search tool
search_tool = TavilySearchResults(
max_results=5,
include_raw_content=True,
)

# Define code tool
def code_tool(code: str) -> str:
"""Execute python code and return the result."""
sbx = Sandbox()
execution = sbx.run_code(code)
if execution.error:
return f"Error: {execution.error}"
return f"Results: {execution.results}, Logs: {execution.logs}"

# Define input schema for stock ticker tool
class TickerToolInput(TypedDict):
"""Input format for the ticker tool.

The tool will pull data in aggregate blocks (timespan_multiplier * timespan) from the from_date to the to_date
"""
ticker: Annotated[str, ..., "The ticker symbol of the stock"]
timespan: Annotated[Literal["minute", "hour", "day", "week", "month", "quarter", "year"], ..., "The size of the time window."]
timespan_multiplier: Annotated[int, ..., "The multiplier for the time window"]
from_date: Annotated[str, ..., "The date to start pulling data from, YYYY-MM-DD format - ONLY include the year month and day"]
to_date: Annotated[str, ..., "The date to stop pulling data, YYYY-MM-DD format - ONLY include the year month and day"]

api_wrapper = PolygonAPIWrapper()
polygon_aggregate = PolygonAggregates(api_wrapper=api_wrapper)

# Define stock ticker tool
def ticker_tool(query: TickerToolInput) -> str:
"""Pull data for the ticker."""
return polygon_aggregate.invoke(query)

定义代理

现在我们已经定义了我们所有的工具,我们可以使用 LangGraph 的 create_react_agent/createReactAgent 来创建我们的代理。

from typing import Optional
from typing_extensions import Annotated, TypedDict

from langgraph.prebuilt import create_react_agent

class AgentOutputFormat(TypedDict):
numeric_answer: Annotated[Optional[float], ..., "The numeric answer, if the user asked for one"]
text_answer: Annotated[Optional[str], ..., "The text answer, if the user asked for one"]
reasoning: Annotated[str, ..., "The reasoning behind the answer"]

agent = create_react_agent(
model="openai:gpt-4o-mini",
tools=[code_tool, search_tool, polygon_aggregates],
response_format=AgentOutputFormat,
state_modifier="You are a financial expert. Respond to the users query accurately",
)

编写测试

现在我们已经定义了我们的代理,让我们编写一些测试以确保基本功能。在本教程中,我们将测试代理的工具调用能力是否正常工作,代理是否知道忽略不相关的问题,以及它是否能够回答涉及使用所有工具的复杂问题。

我们需要首先设置一个测试文件,并在文件顶部添加所需的导入。

创建一个 tests/test_agent.py 文件。

from app import agent, polygon_aggregates, search_tool # import from wherever your agent is defined
import pytest
from langsmith import testing as t

测试 1:处理离题问题

第一个测试将是一个简单的检查,即代理不会对不相关的查询使用工具。

@pytest.mark.langsmith
@pytest.mark.parametrize( # <-- Can still use all normal pytest markers
"query",
["Hello!", "How are you doing?"],
)
def test_no_tools_on_offtopic_query(query: str) -> None:
"""Test that the agent does not use tools on offtopic queries."""
# Log the test example
t.log_inputs({"query": query})
expected = []
t.log_reference_outputs({"tool_calls": expected})

# Call the agent's model node directly instead of running the ReACT loop.
result = agent.nodes["agent"].invoke(
{"messages": [{"role": "user", "content": query}]}
)
actual = result["messages"][0].tool_calls
t.log_outputs({"tool_calls": actual})

# Check that no tool calls were made.
assert actual == expected

测试 2:简单工具调用

对于工具调用,我们将验证代理是否使用正确的参数调用了正确的工具。

@pytest.mark.langsmith
def test_searches_for_correct_ticker() -> None:
"""Test that the model looks up the correct ticker on simple query."""
# Log the test example
query = "What is the price of Apple?"
t.log_inputs({"query": query})
expected = "AAPL"
t.log_reference_outputs({"ticker": expected})

# Call the agent's model node directly instead of running the full ReACT loop.
result = agent.nodes["agent"].invoke(
{"messages": [{"role": "user", "content": query}]}
)
tool_calls = result["messages"][0].tool_calls
if tool_calls[0]["name"] == polygon_aggregates.name:
actual = tool_calls[0]["args"]["ticker"]
else:
actual = None
t.log_outputs({"ticker": actual})

# Check that the right ticker was queried
assert actual == expected

测试 3:复杂工具调用

一些工具调用比其他工具调用更容易测试。使用股票代码查找,我们可以断言搜索了正确的股票代码。使用编码工具,工具的输入和输出的约束要少得多,并且有很多方法可以得到正确的答案。在这种情况下,测试工具是否正确使用的更简单方法是运行完整的代理,并断言它既调用了编码工具,又最终得到了正确的答案。

@pytest.mark.langsmith
def test_executes_code_when_needed() -> None:
query = (
"In the past year Facebook stock went up by 66.76%, "
"Apple by 25.24%, Google by 37.11%, Amazon by 47.52%, "
"Netflix by 78.31%. Whats the avg return in the past "
"year of the FAANG stocks, expressed as a percentage?"
)
t.log_inputs({"query": query})
expected = 50.988
t.log_reference_outputs({"response": expected})

# Test that the agent executes code when needed
result = agent.invoke({"messages": [{"role": "user", "content": query}]})
t.log_outputs({"result": result["structured_response"].get("numeric_answer")})

# Grab all the tool calls made by the LLM
tool_calls = [
tc["name"]
for msg in result["messages"]
for tc in getattr(msg, "tool_calls", [])
]

# This will log the number of steps taken by the agent, which is useful for
# determining how efficiently the agent gets to an answer.
t.log_feedback(key="num_steps", score=len(result["messages"]) - 1)

# Assert that the code tool was used
assert "code_tool" in tool_calls

# Assert that a numeric answer was provided:
assert result["structured_response"].get("numeric_answer") is not None

# Assert that the answer is correct
assert abs(result["structured_response"]["numeric_answer"] - expected) <= 0.01

测试 4:LLM 即法官

我们将通过运行 LLM 即法官评估来确保代理的答案基于搜索结果。为了将 LLM 即法官调用与我们的代理分开跟踪,我们将在 Python 中使用 LangSmith 提供的 trace_feedback 上下文管理器,并在 JS/TS 中使用 wrapEvaluator 函数。

from typing_extensions import Annotated, TypedDict

from langchain.chat_models import init_chat_model

class Grade(TypedDict):
"""Evaluate the groundedness of an answer in source documents."""

score: Annotated[
bool,
...,
"Return True if the answer is fully grounded in the source documents, otherwise False.",
]

judge_llm = init_chat_model("gpt-4o").with_structured_output(Grade)

@pytest.mark.langsmith
def test_grounded_in_source_info() -> None:
"""Test that response is grounded in the tool outputs."""
query = "How did Nvidia stock do in 2024 according to analysts?"
t.log_inputs({"query": query})

result = agent.invoke({"messages": [{"role": "user", "content": query}]})

# Grab all the search calls made by the LLM
search_results = "\n\n".join(
msg.content
for msg in result["messages"]
if msg.type == "tool" and msg.name == search_tool.name
)
t.log_outputs(
{
"response": result["structured_response"].get("text_answer"),
"search_results": search_results,
}
)

# Trace the feedback LLM run separately from the agent run.
with t.trace_feedback():
# Instructions for the LLM judge
instructions = (
"Grade the following ANSWER. "
"The ANSWER should be fully grounded in (i.e. supported by) the source DOCUMENTS. "
"Return True if the ANSWER is fully grounded in the DOCUMENTS. "
"Return False if the ANSWER is not grounded in the DOCUMENTS."
)
answer_and_docs = (
f"ANSWER: {result['structured_response'].get('text_answer', '')}\n"
f"DOCUMENTS:\n{search_results}"
)

# Run the judge LLM
grade = judge_llm.invoke(
[
{"role": "system", "content": instructions},
{"role": "user", "content": answer_and_docs},
]
)
t.log_feedback(key="groundedness", score=grade["score"])

assert grade['score']

运行测试

一旦您设置好配置文件(如果您使用 Vitest 或 Jest),您可以使用以下命令运行测试

Vitest/Jest 的配置文件
ls.vitest.config.ts
import { defineConfig } from "vitest/config";

export default defineConfig({
test: {
include: ["**/*.eval.?(c|m)[jt]s"],
reporters: ["langsmith/vitest/reporter"],
setupFiles: ["dotenv/config"],
},
});
pytest --langsmith-output tests

参考代码

请记住,还要将 VitestJest 的配置文件添加到您的项目中。

代理

代理代码
from typing import Optional

from e2b_code_interpreter import Sandbox
from langchain_community.tools import PolygonAggregates, TavilySearchResults
from langchain_community.utilities.polygon import PolygonAPIWrapper
from langgraph.prebuilt import create_react_agent
from typing_extensions import Annotated, TypedDict

search_tool = TavilySearchResults(
max_results=5,
include_raw_content=True,
)

def code_tool(code: str) -> str:
"""Execute python code and return the result."""
sbx = Sandbox()
execution = sbx.run_code(code)
if execution.error:
return f"Error: {execution.error}"
return f"Results: {execution.results}, Logs: {execution.logs}"

polygon_aggregates = PolygonAggregates(api_wrapper=PolygonAPIWrapper())

class AgentOutputFormat(TypedDict):
numeric_answer: Annotated[
Optional[float], ..., "The numeric answer, if the user asked for one"
]
text_answer: Annotated[
Optional[str], ..., "The text answer, if the user asked for one"
]
reasoning: Annotated[str, ..., "The reasoning behind the answer"]

agent = create_react_agent(
model="openai:gpt-4o-mini",
tools=[code_tool, search_tool, polygon_aggregates],
response_format=AgentOutputFormat,
state_modifier="You are a financial expert. Respond to the users query accurately",
)

测试

测试代码
# from app import agent, polygon_aggregates, search_tool # import from wherever your agent is defined
import pytest
from langchain.chat_models import init_chat_model
from langsmith import testing as t
from typing_extensions import Annotated, TypedDict

@pytest.mark.langsmith
@pytest.mark.parametrize( # <-- Can still use all normal pytest markers
"query",
["Hello!", "How are you doing?"],
)
def test_no_tools_on_offtopic_query(query: str) -> None:
"""Test that the agent does not use tools on offtopic queries."""
# Log the test example
t.log_inputs({"query": query})
expected = []
t.log_reference_outputs({"tool_calls": expected})

# Call the agent's model node directly instead of running the ReACT loop.
result = agent.nodes["agent"].invoke(
{"messages": [{"role": "user", "content": query}]}
)
actual = result["messages"][0].tool_calls
t.log_outputs({"tool_calls": actual})

# Check that no tool calls were made.
assert actual == expected

@pytest.mark.langsmith
def test_searches_for_correct_ticker() -> None:
"""Test that the model looks up the correct ticker on simple query."""
# Log the test example
query = "What is the price of Apple?"
t.log_inputs({"query": query})
expected = "AAPL"
t.log_reference_outputs({"ticker": expected})

# Call the agent's model node directly instead of running the full ReACT loop.
result = agent.nodes["agent"].invoke(
{"messages": [{"role": "user", "content": query}]}
)
tool_calls = result["messages"][0].tool_calls
if tool_calls[0]["name"] == polygon_aggregates.name:
actual = tool_calls[0]["args"]["ticker"]
else:
actual = None
t.log_outputs({"ticker": actual})

# Check that the right ticker was queried
assert actual == expected

@pytest.mark.langsmith
def test_executes_code_when_needed() -> None:
query = (
"In the past year Facebook stock went up by 66.76%, "
"Apple by 25.24%, Google by 37.11%, Amazon by 47.52%, "
"Netflix by 78.31%. Whats the avg return in the past "
"year of the FAANG stocks, expressed as a percentage?"
)
t.log_inputs({"query": query})
expected = 50.988
t.log_reference_outputs({"response": expected})

# Test that the agent executes code when needed
result = agent.invoke({"messages": [{"role": "user", "content": query}]})
t.log_outputs({"result": result["structured_response"].get("numeric_answer")})

# Grab all the tool calls made by the LLM
tool_calls = [
tc["name"]
for msg in result["messages"]
for tc in getattr(msg, "tool_calls", [])
]

# This will log the number of steps taken by the agent, which is useful for
# determining how efficiently the agent gets to an answer.
t.log_feedback(key="num_steps", value=len(result["messages"]) - 1)

# Assert that the code tool was used
assert "code_tool" in tool_calls

# Assert that a numeric answer was provided:
assert result["structured_response"].get("numeric_answer") is not None

# Assert that the answer is correct
assert abs(result["structured_response"]["numeric_answer"] - expected) <= 0.01

class Grade(TypedDict):
"""Evaluate the groundedness of an answer in source documents."""

score: Annotated[
bool,
...,
"Return True if the answer is fully grounded in the source documents, otherwise False.",
]

judge_llm = init_chat_model("gpt-4o").with_structured_output(Grade)

@pytest.mark.langsmith
def test_grounded_in_source_info() -> None:
"""Test that response is grounded in the tool outputs."""
query = "How did Nvidia stock do in 2024 according to analysts?"
t.log_inputs({"query": query})

result = agent.invoke({"messages": [{"role": "user", "content": query}]})

# Grab all the search calls made by the LLM
search_results = "\n\n".join(
msg.content
for msg in result["messages"]
if msg.type == "tool" and msg.name == search_tool.name
)
t.log_outputs(
{
"response": result["structured_response"].get("text_answer"),
"search_results": search_results,
}
)

# Trace the feedback LLM run separately from the agent run.
with t.trace_feedback():
# Instructions for the LLM judge
instructions = (
"Grade the following ANSWER. "
"The ANSWER should be fully grounded in (i.e. supported by) the source DOCUMENTS. "
"Return True if the ANSWER is fully grounded in the DOCUMENTS. "
"Return False if the ANSWER is not grounded in the DOCUMENTS."
)
answer_and_docs = (
f"ANSWER: {result['structured_response'].get('text_answer', '')}\n"
f"DOCUMENTS:\n{search_results}"
)

# Run the judge LLM
grade = judge_llm.invoke(
[
{"role": "system", "content": instructions},
{"role": "user", "content": answer_and_docs},
]
)
t.log_feedback(key="groundedness", score=grade["score"])

assert grade["score"]

此页对您有帮助吗?


您可以留下详细的反馈 在 GitHub 上.