Alpha Notice: These docs cover the v1-alpha release. Content is incomplete and subject to change.For the latest stable version, see the v0 LangChain Python or LangChain JavaScript docs.
Overview
LangChain’screateAgent
runs on LangGraph’s runtime under the hood.
LangGraph exposes a Runtime
object with the following information:
- Context: static information like user id, db connections, or other dependencies for an agent invocation
- Store: a
BaseStore
instance used for long term memory - Stream writer: an object used for streaming information via the
"custom""
stream mode
Access
When creating an agent withcreateAgent
, you can specify a contextSchema
to define the structure of the context
stored in the agent runtime.
When invoking the agent, pass the context
argument with the relevant configuration for the run:
Inside tools
You can access the runtime information inside tools to:- Access the context
- Read or write long term memory
- Write to the custom stream (ex, tool progress / updates)
runtime
parameter to access the Runtime
object inside a tool.
Inside prompt
Use theruntime
parameter to access the Runtime
object inside a prompt function.
Inside pre and post model hooks
Use theruntime
parameter to access the Runtime
object inside a pre or post model hook.