Installation

This guide covers installation scenarios for LangCrew, from basic setup to development.

Basic Installation

Using pip

The simplest way to install LangCrew:

pip install langcrew

Using uv (Recommended)

For faster, more reliable installations:

uv add langcrew

Verify Installation

import langcrew
print(f"LangCrew version: {langcrew.__version__}")

LLM Configuration

LangCrew requires an LLM provider. Configure your API keys as environment variables:

OpenAI

export OPENAI_API_KEY=your_openai_key
export OPENAI_BASE_URL=https://api.openai.com/v1  # Optional

from langchain_openai import ChatOpenAI

llm = ChatOpenAI(model="gpt-4o")

Anthropic

export ANTHROPIC_API_KEY=your_anthropic_key

from langchain_anthropic import ChatAnthropic

llm = ChatAnthropic(model="claude-3-5-sonnet-20241022")

DashScope (Alibaba)

export DASHSCOPE_API_KEY=your_dashscope_key

from langchain_community.chat_models import ChatTongyi

llm = ChatTongyi(model="qwen-max")

Google Gemini

export GOOGLE_API_KEY=your_google_key

from langchain_google_genai import ChatGoogleGenerativeAI

llm = ChatGoogleGenerativeAI(model="gemini-pro")

Troubleshooting

Common Issues

Import Error: Cannot import langcrew

Solution: Ensure you’re in the correct virtual environment and LangCrew is installed:

pip install --upgrade langcrew

LLM API Key Not Found

Solution: Verify environment variables are set:

echo $OPENAI_API_KEY

If empty, set it:

export OPENAI_API_KEY=your_key

Next Steps

• Quick Start Guide - Build your first agent crew
• Core Concepts - Understand the framework fundamentals
• Memory Guide - Configure persistence and memory