Python vs TypeScript for AI Agents
Python has the deepest agent ecosystem, but TypeScript is catching up fast. What you gain and give up on each side in 2026.
For most of the agent era, the answer to "what language do I build agents in" was Python, and it was not close. In 2026 that is still mostly true, but TypeScript has gone from an afterthought to a real option. If you are choosing a language for an agent project, here is the honest trade-off.
Why Python leads
Python has the deepest agent ecosystem by a wide margin. LangGraph, CrewAI, LlamaIndex, AutoGen, Pydantic AI, Google ADK, Semantic Kernel, and Smolagents all support it, and most new research and tooling lands in Python first. If you want the most integrations, the most examples, and the most Stack Overflow answers, Python wins. The data and machine-learning ecosystem also lives in Python, which matters if your agent touches models, embeddings, or analysis directly.
Why TypeScript is catching up
The case for TypeScript is the rest of your stack. If your product is a web app, your team already writes TypeScript, and putting the agent in the same language avoids a separate Python service, a second deployment, and a serialization boundary between them. Mastra is built natively in TypeScript with workflows, memory, and evals, and LangGraph, LlamaIndex, and the OpenAI Agents SDK all have TypeScript versions. Agents that live at the edge or in serverless functions are also easier in the JavaScript world.
What you give up on each side
Choosing Python means you may run the agent as a separate service from a TypeScript front end, with the operational overhead that brings. Choosing TypeScript means a younger ecosystem: fewer third-party integrations, fewer examples, and occasionally waiting for a feature that landed in Python first. Neither gap is fatal, and the TypeScript gap shrinks every quarter.
How to decide
Match the agent to your existing stack unless you have a strong reason not to. A Python team building a data-heavy agent should stay in Python. A TypeScript team shipping a web product should look hard at Mastra or the TypeScript ports before standing up a Python service. The cost of crossing languages is usually higher than the marginal ecosystem advantage.