Mastra

// Overview

Mastra is an open-source framework for building AI-powered applications and agents on a modern TypeScript stack. It bundles the common pieces of an AI app — agents, a workflow engine, memory, retrieval (RAG), and observability — so you can go from a prototype to a production service without stitching the parts together yourself.

It is built for TypeScript developers who work with React, Next.js, or Node. You can drop Mastra agents and workflows into an existing app, or run them as a standalone server. A model router lets you reach providers like OpenAI, Anthropic, and Gemini through one interface, so you are not locked to a single vendor.

As a general agent framework, Mastra covers both ends of the control spectrum: autonomous agents that decide which tools to call and iterate on their own, and graph-based workflows for cases where you need explicit, step-by-step execution. It can also expose your agents and tools as MCP servers for other systems to use.

// What it does

• Model routing to 40+ providers (OpenAI, Anthropic, Gemini, and more) through one standard interface
• Autonomous agents that reason about goals, choose tools, and iterate until a final answer or stopping condition
• Graph-based workflow engine with control-flow syntax like .then(), .branch(), and .parallel()
• Human-in-the-loop suspend-and-resume backed by storage, so a run can pause and continue later
• Context management with conversation history, RAG retrieval, and Observational Memory
• Author MCP servers and ship with built-in evals and observability for production

// Getting started

The recommended way to start is the create-mastra CLI, which scaffolds a new project and walks you through setup.

npm create mastra@latest

npm run dev

Commands and code are distilled from the project's own documentation — always check the official repo for the latest.

// When to use it

• Build an autonomous agent that uses tools to answer open-ended user requests
• Orchestrate a multi-step process with explicit branching and parallel steps using the workflow engine
• Add a RAG-backed assistant with conversation memory to a React or Next.js app
• Expose your agents and tools as an MCP server for other agents and systems to consume

// How Mastra compares

Mastra alongside other open-source agent frameworks & builders tools AI/TLDR tracks, ranked by GitHub stars.