SDKs and harnesses for building agents, from OpenAI and Mastra to OpenHands.
Latest launch
Frameworks are what you build an agent with: a harness, a controller, or a workspace for running other agents. Hosted APIs that wrap a harness are filed under agent infra when the product is the service rather than the library.
adk-pythonGoogle's adk-python v2.12.0, released October 13, 2026, adds after_tool_callback, require_confirmation, custom Agent Engine service accounts and Python 3.15.
Category: Frameworks
Pricing: Open source
MastraMastra's @mastra/core 1.76.0, published October 13, 2026, makes durable agent crash recovery safe across instances and adds atomic Postgres memory merges.
Category: Frameworks
Pricing: Open source
AgnoAgno v3.1.3, released October 12, 2026, adds background runs, retries, metrics and structured output to ClaudeAgent and CodexAgent external agents.
Category: Frameworks
Pricing: Open source
DSPyDSPy 3.4.1, released October 12, 2026, makes GEPA's structured InstructionProposer the default and lets dspy.RLM build DSPy sub-agents.
Category: Frameworks
Pricing: Open source
LangChainlangchain-anthropic 1.7.6, released October 12, 2026, declares mid-conversation support in model profiles and bumps langgraph-sdk and urllib3.
Category: Frameworks
Pricing: Open source
LangGraphLangGraph 1.2.15, published October 12, 2026, is a fix release that tightens DeltaChannel, checkpoint, interrupt and ToolNode resume handling.
Category: Frameworks
Pricing: Open source
OpenHandsOpenHands 1.27.0 adds an agent-assisted automation setup flow, persisted drafts, and a link from Agent Canvas to DigitalOcean Managed Agents.
Category: Frameworks
Pricing: Open source
CrewAICrewAI 1.15.27, released October 9, 2026, adds a deepinfra provider, per-run cost and time tracking in crewai eval, and several bug fixes.
Category: Frameworks
Pricing: Open source
Pydantic AIPydantic AI 2.55.0, released October 9, 2026, requires Python 3.11 and adds Conversation, a unified cache setting and Postgres stores.
Category: Frameworks
Pricing: Open source
MastraMastra extracted the loop around Mastra Code into AgentController, shipping in @mastra/core 1.47.0 on June 18, 2026.
Category: Frameworks
Pricing: Open source
OpenAI AgentsOn April 15, 2026, OpenAI's Agents SDK gained a sandbox-aware harness for files, commands, and long-running tasks. Python shipped first.
Category: Frameworks
Pricing: Open source
Apache-2.0 · Open source
An open-source, code-first Python toolkit for building, evaluating and deploying AI agents.
Apache-2.0 · Open source · MCP
Agno is an orchestration and service layer for agents, exposing them through a REST API and an MCP server.
MIT · Open source
CrewAI is a framework for orchestrating role-playing, autonomous AI agents that work together.
MIT · Open source
DSPy is a framework for programming, not prompting, language models, maintained in stanfordnlp/dspy.
MIT · Open source
LangChain is an open-source agent engineering platform and Python framework for building agents.
MIT · Open source
LangGraph is an open-source orchestration runtime for building stateful, resilient agents.
Open source
TypeScript agent framework. Mastra Code is the terminal agent; AgentController is the extracted loop, in @mastra/core 1.47.0 or later.
MIT · Open source
Pydantic AI is a model-agnostic Python framework for building typed AI agents and applications.