Context editing middleware.
Mirrors Anthropic's context editing capabilities by clearing older tool results once the conversation grows beyond a configurable token threshold.
The implementation is intentionally model-agnostic so it can be used with any LangChain chat model.
Base middleware class for an agent.
Subclass this and implement any of the defined methods to customize agent behavior between steps in the main agent loop.
State schema for the agent.
Model request information for the agent.
Response from model execution including messages and optional structured output.
The result will usually contain a single AIMessage, but may include an additional
ToolMessage if the model used a tool for structured output.
Protocol describing a context editing strategy.
Configuration for clearing tool outputs when token limits are exceeded.
Automatically prune tool results to manage context size.
The middleware applies a sequence of edits when the total input token count exceeds configured thresholds.
Currently the ClearToolUsesEdit strategy is supported, aligning with Anthropic's
clear_tool_uses_20250919 behavior (read more).
