Best LiteLLM Alternatives in 2026

Vercel AI SDK is an open-source TypeScript toolkit for building AI-powered applications and agents. It provides a unified API across 20+ model providers, streaming UI hooks for React and Vue, structured output with Zod, and a full agent abstraction layer.

BentoML is an open-source Python framework for packaging and deploying machine learning models as production APIs. It supports any ML framework, includes OpenLLM for self-hosted LLM serving, and offers BentoCloud for managed inference with autoscaling and BYOC.

Genkit is Google's open-source AI framework for TypeScript, Go, and Python developers. It provides typed flows, RAG, tool calling, and multi-agent support with a standout local Developer UI for iterating prompts and debugging traces. Free under Apache 2.0.

Helicone is an open-source LLM observability platform and AI gateway from YC W23. One URL swap gives teams cost tracking, request logging, semantic caching, and prompt management across OpenAI, Anthropic, and 100+ models. Used by 16,000 organizations before its March 2026 acquisition by Mintlify.

PydanticAI is an open-source Python framework for building production-grade AI agents. Created by Samuel Colvin (creator of Pydantic), it brings FastAPI-style type safety, structured outputs, and dependency injection to agent development. Free, MIT-licensed, 16k+ GitHub stars.

Modal is a serverless GPU platform that lets Python developers run AI workloads on cloud GPUs without touching infrastructure. Write a function, add a decorator, and Modal handles containers, scaling, and billing down to the second.

smolagents is Hugging Face's open-source Python library for building AI agents that write code as actions rather than JSON tool calls. Apache 2.0, ~1,000 lines of core code, supports 100-plus LLMs including local models via Ollama and Transformers.

Kong AI Gateway is the LLM and agent traffic-governance layer on Kong's open-source API gateway, unifying routing, token quotas, caching, PII guards, and observability. By 2026 it governs LLM, MCP, and agent-to-agent traffic from one control plane.

Letta is the open-source agent framework from UC Berkeley's MemGPT research team. It gives AI agents persistent, self-editable memory using an OS-inspired three-tier architecture. Apache 2.0 with a cloud-hosted API option.

OpenAI's official open-source framework for multi-agent workflows. Launched March 2025 as the production successor to Swarm. Provides handoffs, guardrails, tracing, and voice agent support in Python and TypeScript.