LLM SDKs and routers
Code libraries and gateways for calling language models from your app, often across several providers through one interface.
Search AirStackWhy teams use it
- Switch or combine model providers without rewriting code
- Fall back to another model when one is down or slow
- Track usage and cost per team, app or customer
- Streaming, retries and structured output handled for you
Who uses it: AI engineer, Software engineer, Back-end engineer, Platform engineer, ML engineer. Watch for: A layer between you and the provider can lag new model features; check how quickly it supports the options you rely on. AirStack’s guide to the category.
10 products
| Product | What it says it does | Starting at |
|---|---|---|
| Portkey | Connect, manage, and secure AI interactions across 3000+ LLMs with centralized control, real-time monitoring, and enterprise-grade… | Not observed |
| LiteLLM | LiteLLM is one gateway for all your models, tools, and agents. | Not observed |
| OpenRouter | The Unified Interface For Every Model | Not observed |
| OpenAI SDK | The official Python library for the OpenAI API | Not observed |
| Vercel AI SDK | The TypeScript toolkit for building AI applications and agents. | Not observed |
| LlamaIndex | AI Agents for Document OCR + Workflows | Not observed |
| Google Gen AI SDK | Google Gen AI Python SDK provides an interface for developers to integrate | Not observed |
| Anthropic SDK | The Claude SDK for Python provides access to the Claude API from Python applications. | Not observed |
| LangChain | LangChain provides create_agent: a minimal, highly configurable agent harness. | Not observed |
| Mistral SDK | Install the SDK, set your API key, and get a model response. | Not observed |
Prices are list prices as written on each pricing page; hover one for its quote. “Not observed” means AirStack has not found it on that product’s pages.
Open models for the job
- openai-community/gpt2 30,091,264 downloads in 30 days · mit
- Qwen/Qwen3-0.6B 22,322,522 downloads in 30 days · apache-2.0
- Qwen/Qwen3-14B 12,949,368 downloads in 30 days · apache-2.0