AI Agents with LangChain & Autonomous Workflows · レッスン

トレーシングと監視のためのLangSmith

LangSmithを使って、エージェントの思考プロセス、ツールの使用状況、実行フロー全体を可視化します。

「トレーシングと監視のためのLangSmith」はCoddyKit上の無料AI Agents with LangChain & Autonomous Workflowsレッスンです。これはレッスン1/4です。下記で完全なレッスンを無料で読むことができます。その後、ブラウザ内の組み込みコードエディタと24時間対応のAIチューターでハンズオン演習できます。これはAI Agents with LangChain & Autonomous Workflows学習パスの一部であり、ウェブとCoddyKitアプリ全体で進捗が同期されます。 AI Agents with LangChain & Autonomous Workflowsコースには全4レッスンが含まれています。

このレッスンの一部はまだ翻訳されておらず、英語で表示されています。

Seeing Inside Your Agent

When you build an AI agent, it often feels like a black box. You provide an input, and it gives an output, but what happens in between?

Did it understand your prompt correctly?
Which tools did it decide to use?
Why did it choose that particular action?

Understanding these internal workings is crucial for debugging and improving your agents.

Introducing LangSmith

LangSmith is a developer platform by LangChain, designed specifically for building, debugging, and evaluating Large Language Model (LLM) applications.

It provides the visibility you need to understand your agent's behavior, identify issues, and ensure it performs as expected.

Core Concepts: Traces & Runs

In LangSmith, two key concepts are Runs and Traces:

A Run represents a single execution of a component, like an LLM call, a tool invocation, or a chain step.
A Trace is a collection of related runs that together form a complete execution of your agent or application, showing the full sequence of events.

Imagine a trace as a detailed log of your agent's entire thought process and actions.

Setting Up LangSmith

To use LangSmith, you need to set a few environment variables:

LANGCHAIN_TRACING_V2=true: Enables LangSmith tracing.
LANGCHAIN_API_KEY: Your unique API key for authentication.
LANGCHAIN_PROJECT: A name for your project to group related traces.

You can get your API key from the LangSmith website after signing up.

Enabling Tracing in Code

Let's see how to enable tracing for a simple LangChain application. First, ensure you have your API key and project name set up.

import os
from langchain_openai import ChatOpenAI
from langchain_core.prompts import ChatPromptTemplate

# Set these environment variables before running
os.environ["LANGCHAIN_TRACING_V2"] = "true"
os.environ["LANGCHAIN_API_KEY"] = "YOUR_LANGSMITH_API_KEY"
os.environ["LANGCHAIN_PROJECT"] = "MyFirstLangSmithProject"

# Replace with your actual OpenAI API key
os.environ["OPENAI_API_KEY"] = "YOUR_OPENAI_API_KEY"

# Create a simple LLM chain
llm = ChatOpenAI(model="gpt-3.5-turbo", temperature=0)
prompt = ChatPromptTemplate.from_messages([
    ("system", "You are a helpful assistant."),
    ("user", "{question}")
])
chain = prompt | llm

# Invoke the chain
response = chain.invoke({"question": "What is the capital of France?"})
print(response.content)

Viewing Your First Trace

After running the previous code, a trace will be sent to your LangSmith project. Navigate to the LangSmith UI (app.langsmith.com) and select your project.

You'll see a visual representation of the 'chain' execution, including:

The input to the prompt.
The LLM call itself.
The final output from the LLM.

Each step is a 'Run' within the 'Trace'.

Understanding Agent Thought Process

For more complex agents, LangSmith shines by showing the agent's thought process. You can see the sequence of:

Thought: The agent's reasoning.
Action: The tool it decided to use.
Action Input: The arguments passed to the tool.
Observation: The result returned by the tool.

This detailed breakdown helps you understand why an agent made certain decisions.

Monitoring Tool Usage

Agents often rely on various tools (e.g., search engines, calculators, custom APIs). LangSmith traces clearly show:

Which specific tools were called.
The exact inputs provided to each tool.
The outputs received from the tools.

This is invaluable for verifying that your agent is using tools correctly and for debugging when a tool returns an unexpected result.

Debugging with LangSmith Traces

Traces are your best friend for debugging. If your agent behaves unexpectedly:

Identify the exact step: Pinpoint where the incorrect logic or error occurred.
Inspect inputs/outputs: Check if the prompt received the expected input or if the tool returned the right output.
Review agent thoughts: Understand if the agent's reasoning led to a bad decision.

This visibility dramatically reduces debugging time compared to traditional print statements.

Check Your Knowledge

Which of the following is NOT a primary benefit of using LangSmith for AI agents?

Recap: Your Observability Ally

LangSmith is an essential tool for anyone building AI agents with LangChain. It transforms the black box of agent execution into a transparent, inspectable process.

By providing detailed traces of runs, agent thoughts, and tool usage, LangSmith empowers you to debug faster, understand your agents better, and build more robust and reliable AI applications.

よくある質問

「トレーシングと監視のためのLangSmith」レッスンは無料ですか？

はい。「トレーシングと監視のためのLangSmith」の完全なテキストはこのウェブで無料で読めます。インタラクティブに演習し（組み込みコードエディタと24時間対応のAIチューター）、AI Agents with LangChain & Autonomous Workflowsコースの残りをアンロックするには、CoddyKit PROにアップグレードしてください。 AI Agents with LangChain & Autonomous Workflowsコースには全4レッスンが含まれています。

「トレーシングと監視のためのLangSmith」で何を学びますか？

LangSmithを使って、エージェントの思考プロセス、ツールの使用状況、実行フロー全体を可視化します。ブラウザで直接実行するハンズオンコードでAI Agents with LangChain & Autonomous Workflowsを演習し、24時間対応のAIチューターがレッスンを進める中での質問に答えます。

AI Agents with LangChain & Autonomous Workflowsを始めるのに経験は必要ですか？

事前経験は必要ありません。CoddyKitのAI Agents with LangChain & Autonomous Workflowsは初級者から上級者向けに構成されているため、ここから始めるか最初から始めて、自分のペースで進むことができます。これはレッスン1/4です。

「トレーシングと監視のためのLangSmith」レッスンにはどのくらい時間がかかりますか？

ほとんどのCoddyKitレッスンは約5～10分かかります。各レッスンはコンパクトでインタラクティブなので、着実に進歩し、ウェブとアプリ全体で正確に前回の場所から再開できます。

このAI Agents with LangChain & Autonomous Workflowsレッスンでコードを書いて実行できますか？

はい。すべてのAI Agents with LangChain & Autonomous Workflowsレッスンに組み込みコードエディタが含まれているため、ブラウザでリアルコードを書いて実行し、即座のAIフィードバックを取得できます。ローカル設定は不要です。

このコースのすべてのレッスン

← AI Agents with LangChain & Autonomous Workflowsに戻る