LangChain Agent Framework

Async event-streaming agents, composable hierarchies, session management, planners, and first-class A2A & MCP integration. No LangGraph required.

pip install langchain-adk

Async Event Streaming

Every agent is an async generator yielding typed events — thoughts, tool calls, results, streaming chunks. Built for real-time UIs.

Nest agents freely. Chain them sequentially, run in parallel, loop until done, or wrap as tools. Plain Python asyncio.

Per-turn planning hooks inject dynamic instructions and post-process responses. Built-in PlanReAct and TaskPlanner included.

Pluggable session service persists events and state deltas automatically. In-memory included, bring your own database.

Function tools, agent-as-tool, transfer handoffs, exit loop, long-running tools, and tool confirmation — all built in.

First-class tracing via AgentConfig callbacks. Works with Langfuse, LangSmith, or any LangChain callback handler.

pip install langchain-adk[openai]

pip install langchain-adk[anthropic]

pip install langchain-adk[google]

pip install langchain-adk
# + your preferred langchain-* provider package

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