langchain-serpex-python

This package contains the LangChain integration with Serpex (Python).

Installation

pip install langchain-serpex-python

What is Serpex?

Serpex is a real-time web search API. It returns structured JSON results (title, URL, snippet) for any query, and offers page content extraction that turns URLs into LLM-ready markdown. It's built for AI agents, LLM tools and RAG pipelines.

Features

• Real-time web search: current results for any query
• One search engine: nothing to configure — no engine to pick
• LangChain-native: a drop-in BaseTool for agents and chains
• Easy integration: API key via argument or SERPEX_API_KEY

Quick Start

Get Your API Key

Sign up at SERPEX to get your API key.

Basic Usage

from langchain_serpex_python import SerpexSearchResults

# Initialize the tool
tool = SerpexSearchResults(api_key="your-serpex-api-key")

# Perform a search
results = tool.invoke("latest AI developments")
print(results)

With Agents

from langchain_serpex_python import SerpexSearchResults
from langchain_openai import ChatOpenAI
from langchain.agents import initialize_agent, AgentType

# Initialize the search tool
search_tool = SerpexSearchResults(api_key="your-serpex-api-key")

# Initialize the LLM
llm = ChatOpenAI(temperature=0)

# Create an agent with the search tool
agent = initialize_agent(
    tools=[search_tool],
    llm=llm,
    agent=AgentType.ZERO_SHOT_REACT_DESCRIPTION,
    verbose=True
)

# Run the agent
result = agent.run("What are the latest developments in quantum computing?")
print(result)

Advanced Configuration

from langchain_serpex_python import SerpexSearchResults

# Configure with advanced parameters
tool = SerpexSearchResults(
    api_key="your-serpex-api-key",
    time_range="month"
)

results = tool.invoke("best restaurants")
print(results)

The engine parameter (deprecated)

Serpex is one search engine, so there is nothing to select. engine is deprecated and ignored by the Serpex API since 2026-06; it is still accepted so existing code keeps working.

Configuration

Environment Variables

You can set your SERPEX API key as an environment variable:

export SERPEX_API_KEY="your-serpex-api-key"

Then use the tool without passing the API key:

from langchain_serpex_python import SerpexSearchResults

tool = SerpexSearchResults()  # Will use SERPEX_API_KEY from environment

Parameters

• api_key (str): Your Serpex API key (required)
• engine (str): Deprecated — ignored by the Serpex API (default: "auto"); still accepted
• category (str): Search category - currently only "web" is supported (default: "web")
• time_range (str): Time filter - "all", "day", "week", "month", "year"

Documentation

For more detailed documentation, visit:

• LangChain Documentation
• SERPEX API Documentation

Support

For issues and questions:

• GitHub Issues: langchain-serpex issues
• SERPEX Support: support@serpex.dev

License

This package is licensed under the MIT License.

CI / Publishing

A GitHub Actions workflow is provided to publish the package to PyPI when a tag like v* is pushed or when a release is published.

Required repository secret:

• PYPI_API_TOKEN — a PyPI API token with permission to upload the package. Set this in the repository's Settings → Secrets → Actions.

To publish a new release, create a tag vMAJOR.MINOR.PATCH and push it or create a release in GitHub; the workflow will build sdist and wheel and upload them to PyPI.