Mastra
TypeScript-first AI agent framework with built-in workflows
Verdict
Clean TypeScript SDK for building agents with workflows, tools, and RAG. Good DX with VS Code extension. Newer framework with growing ecosystem. Worth watching for TS-first teams.
Other Frameworks & SDKs
- DSPyStable
Stanford framework for programming (not prompting) LMs
- GuidanceExperimental
Microsoft's constrained generation library for structured LLM output
- HaystackStable
Deepset open-source NLP framework for production LLM pipelines
- InstructorProduction
Structured outputs from LLMs using Pydantic schemas
- LMQLExperimental
Query language for LLMs — SQL-like syntax for constrained generation
- LangChainProduction
Composable LLM application framework — chains, agents, RAG

