Mastra

Overview

Mastra is an open-source, TypeScript-native framework for building production-grade AI agents and AI-powered applications. Developed by mastra-ai, it provides a modern developer experience with built-in agent orchestration, workflow management, memory, and tool integrations—all designed for the JavaScript/TypeScript ecosystem.

With over 26,000 GitHub stars, Mastra has become one of the most popular choices for full-stack developers who prefer to build AI agents in TypeScript rather than Python. It offers a modular architecture that separates concerns between agent logic, workflows, memory, and runtime, enabling teams to scale from simple agents to complex multi-agent systems.

Features

• Agent Orchestration: Create agents with custom system prompts, tools, and memory
• Workflow Engine: Compose agents into multi-step workflows with conditional branching and loops
• Memory System: Built-in short-term and long-term memory with vector store integration
• Tool System: First-class tool definitions with TypeScript types and auto-validation
• Multi-Provider LLM Support: OpenAI, Anthropic, Google, local models via a unified provider API
• Streaming Support: Real-time token streaming for agent responses
• Observability: Built-in tracing and logging for agent execution
• Dev Server: Hot-reloading development server for rapid iteration

Installation

npm install @mastra/core
# or
yarn add @mastra/core

Quick Start

import { Agent } from '@mastra/core';

const myAgent = new Agent({
  name: 'research-assistant',
  instructions: 'You are a helpful research assistant.',
  tools: { search, analyze },
  memory: memoryStore,
});

const response = await myAgent.run('Research quantum computing advances');

Core Concepts

Agent

An Agent combines system instructions, tools, memory, and an LLM provider into an executable unit.

Workflow

Workflows orchestrate multiple agents and tasks in sequence or parallel, with conditionals and error handling.

Memory

Mastra provides multiple memory strategies: in-memory (ephemeral), vector stores (semantic), and SQL (structured).

Advanced Features

Multi-Agent Workflows

import { Workflow } from '@mastra/core';

const workflow = new Workflow()
  .step(researchAgent.run)
  .step(analysisAgent.run)
  .step(summaryAgent.run);

Custom Tool Types

const weatherTool = new Tool({
  name: 'getWeather',
  description: 'Get current weather',
  inputSchema: z.object({ city: z.string() }),
  execute: async ({ city }) => { /* ... */ },
});

Examples

• Customer Support Agent: Handles ticket triage, knowledge base lookup, and escalation
• Content Pipeline: Research → Draft → Review → Publish workflow
• Code Assistant: Combines code search, generation, and testing agents

Pros

• ✅ TypeScript-native with full type safety
• ✅ Modular architecture scales from simple to complex
• ✅ Built-in memory and workflow primitives
• ✅ Multi-provider LLM abstraction
• ✅ Excellent developer experience

Cons

• ❌ Primarily JavaScript/TypeScript ecosystem
• ❌ Newer project with less battle-testing than LangGraph or AutoGen
• ❌ Smaller community than Python alternatives

When to Use

Use Mastra when building AI agents in a TypeScript/JavaScript codebase, especially full-stack applications that need tight integration between frontend and agent logic. Ideal for teams invested in the Vercel/Next.js ecosystem.

Resources

• Official Docs
• GitHub Repository
• Examples