agent-framework
(4)
Letta
Letta is a San Francisco AI research lab and platform for building stateful agents - AI that remembers, learns, and improves itself over time. Spun out of UC Berkeley's Sky Computing Lab from the viral MemGPT project, Letta gives developers an open framework, API, and cloud service where agent state (memories, messages, reasoning, tool calls) is persisted in a database rather than lost when it falls out of the context window. The company positions itself as the open alternative for developers who want to build agents that behave less like stateless chatbots and more like continuously learning digital collaborators.
Mastra
Mastra is an open-source TypeScript framework for building production-ready AI agents, workflows, and retrieval-augmented generation pipelines. Built by the team behind Gatsby, it gives developers agents, durable workflows, memory, RAG, tool calling, evals, and observability in one stack - so JavaScript and TypeScript engineers can move from prototype to production without leaving their language. Mastra is developed by Kepler Software, a San Francisco startup, and reached 25,000+ GitHub stars and 300,000+ weekly npm downloads with adoption at companies like Brex, Sanity, Replit, and PayPal.
Lyzr AI
Lyzr AI is an enterprise agent-infrastructure company that helps banks, insurers, and other regulated organizations move AI agents from proof-of-concept to production. Its open-core Agent Framework bakes Safe AI and Responsible AI modules into the core architecture, while products like Agent Studio and a roster of named agents (Jazon the AI SDR, Skott the AI marketer) let teams build, govern, and deploy autonomous agents inside their own firewall or VPC. Backed by Accenture and valued at $250M, Lyzr positions itself as the trusted layer between large language models and the compliance-bound enterprise.
SuperAGI
SuperAGI is a Palo Alto-based AI company building autonomous agents that run real work - sales outreach, software engineering, marketing, support - on a single platform. Founded by Ishaan Bhola and Mukunda NS, it began as an open-source agent framework on GitHub and grew into a 25+ app super-platform used by SMB and enterprise teams, backed by $10M Series A from Jan Koum's Newlands VC.