llama-index-llms-anthropic

What it is and what it does

This package provides a LlamaIndex integration for Anthropic's Claude language models, allowing developers to use Claude within the LlamaIndex framework for text generation tasks. It wraps the anthropic client library and exposes Claude through LlamaIndex's standard LLM interface, supporting both synchronous and asynchronous operations.

The integration handles model configuration, API key management, and token counting specific to Claude's tokenizer. It supports multiple interaction patterns: simple text completion, multi-turn chat with message history, streaming responses for real-time output, structured prediction to extract typed objects from model responses, and tool use including web search capabilities. Developers can also route requests through Vertex AI if preferred.

Use it for:

• Build a LlamaIndex RAG pipeline that uses Claude for retrieval-augmented generation over custom documents.
• Create a chatbot with multi-turn conversation history using Claude through LlamaIndex's chat interface.
• Extract structured data from unstructured text by using Claude's structured prediction to generate typed Pydantic models.
• Stream Claude responses in real-time to a user interface while processing long-form text generation.
• Integrate web search capabilities into Claude completions for fact-checking or current-information queries.

Worth the install?

AI-flagged interpretation of the facts on this page — verify before relying

Integrates Anthropic's Claude language models into LlamaIndex applications, enabling text completion, chat, streaming, and structured prediction workflows.

Yes. The package has low install friction, active maintenance, permissive MIT licensing, no known vulnerabilities, and integrates cleanly into LlamaIndex workflows. Install it if you are building LlamaIndex applications and want to use Claude models; skip it if you are using Anthropic's SDK directly without LlamaIndex.

Install

llama-index-llms-anthropic on PyPI

pip install llama-index-llms-anthropic

uv add llama-index-llms-anthropic

poetry add llama-index-llms-anthropic

Installing llama-index-llms-anthropic

Before you install

Low friction install with only two runtime dependencies (anthropic and llama-index-core). Package is actively maintained with a recent release.

License in practice

MIT license permits unrestricted use, modification, and distribution with minimal restrictions.

Quickstart

pip install llama-index-llms-anthropic

import os
from llama_index.llms.anthropic import Anthropic

os.environ["ANTHROPIC_API_KEY"] = "your-key"
llm = Anthropic(model="claude-3-opus-20240229")
resp = llm.complete("Paul Graham is ")
print(resp)

Requires a valid Anthropic API key set in the ANTHROPIC_API_KEY environment variable or passed directly to the Anthropic constructor.

Verify before relying

• Whether the 180k token limit mentioned for Claude 3 in the description applies to all Claude models or only specific versions.
• Current status of Claude 3 tokenizer updates since the description notes it has not been updated yet.
• Specific performance characteristics or latency expectations when used with LlamaIndex.

Package facts

Evidence: llama_index_llms_anthropic-0.11.10-py3-none-any.whl

Tags

More Artificial Intelligence packages

Further reading