> ## Documentation Index
> Fetch the complete documentation index at: https://docs.ambientmeta.com/llms.txt
> Use this file to discover all available pages before exploring further.

# LangChain Integration

> Safely use LangChain with any LLM without exposing PII

## Install

```bash theme={null}
pip install langchain-ambientmeta
```

## Quick Start

```python theme={null}
from langchain_ambientmeta import PrivacyLLM
from langchain_openai import ChatOpenAI

# Wrap your LLM with privacy protection
safe_llm = PrivacyLLM(
    llm=ChatOpenAI(model="gpt-4"),
    api_key="am_live_xxx",
)

# Use normally — PII is automatically handled
response = safe_llm.invoke("Summarize John Smith's file at john@acme.com")
# OpenAI never sees the real PII
```

<Tip>
  **That's it!** The wrapper automatically sanitizes input, calls the LLM with safe text, and rehydrates the response.
</Tip>

## How It Works

1. Your input is sanitized before reaching the LLM
2. The LLM processes the sanitized text
3. The response is rehydrated with original entities
4. You get back the complete response

## With Chains (LCEL)

```python theme={null}
from langchain_core.prompts import ChatPromptTemplate

prompt = ChatPromptTemplate.from_template("Answer this question: {query}")
chain = prompt | safe_llm

result = chain.invoke({"query": "What is John Smith's email?"})
```

## With RAG

```python theme={null}
from langchain.chains import create_retrieval_chain
from langchain.chains.combine_documents import create_stuff_documents_chain
from langchain_core.prompts import ChatPromptTemplate

prompt = ChatPromptTemplate.from_template(
    "Answer the question based on context:\n{context}\n\nQuestion: {input}"
)
combine_chain = create_stuff_documents_chain(safe_llm, prompt)
rag_chain = create_retrieval_chain(your_retriever, combine_chain)

result = rag_chain.invoke({"input": "Find information about employee EMP-123456"})
```

## Configuration

```python theme={null}
safe_llm = PrivacyLLM(
    llm=ChatOpenAI(model="gpt-4"),
    api_key="am_live_xxx",
    entities=["PERSON", "EMAIL_ADDRESS", "SSN"],  # Optional: specific entities only
    auto_rehydrate=True,   # Automatically restore PII in responses (default: True)
)
```