Haystack Integration

Haystack by deepset is an open-source framework for building production-ready LLM applications, RAG pipelines, and search systems. It provides modular components for document processing, retrieval, and generation.

Haystack's OpenAI generators support custom base URLs.

Prerequisites

An LLM API account with an API key
Haystack installed or accessible

Setup

Get Your LLM API Key

Log in to your LLM API dashboard
Click Create Key to Start
Copy your new API key immediately — it will only be shown once
Store the key securely (e.g., in a password manager or .env file)

LLM API is an OpenAI-compatible gateway that gives you access to dozens of AI models through a single API key and endpoint.

Configure LLM API in Haystack

Install Haystack:

pip install haystack-ai

Configure:

from haystack.components.generators.chat import OpenAIChatGenerator
generator = OpenAIChatGenerator(
model="openai/gpt-4o",
api_key=Secret.from_token("your-llm-api-key-here"),
api_base_url="https://api.llmapi.ai/v1"
)

Use the generator in your Haystack pipeline.

Test the Integration

Verify that Haystack can successfully communicate with LLM API by sending a test request. All requests will now be routed through LLM API.

Haystack's pipeline architecture lets you combine LLM API models with retrievers and preprocessors.

Benefits of Using LLM API with Haystack

Multi-Provider Access: Use models from OpenAI, Anthropic, Google, and more through a single API
Cost Control: Track and limit your AI spending with detailed usage analytics
Unified Billing: One account for all providers instead of managing multiple API keys
Caching: Reduce costs with response caching for repeated requests

View all available models on the models page.