Observations
Observations are the results returned to the agent after executing an action — tool outputs, API responses, or environment state — that the LLM uses to reason about the next step.
What is Observations?
Observations are the results returned to the agent after executing an action — tool outputs, API responses, or environment state — that the LLM uses to reason about the next step.
Observations are the results returned to the agent after executing an action — tool outputs, API responses, or environment state — that the LLM uses to reason about the next step.
Where is it used?
In ReAct, observations are appended as a `tool` message; in LangGraph, `ToolNode` returns observation messages; web agents observe DOM screenshots or HTML text after a browser action.
How to build it
After executing a tool, append `{"role": "tool", "content": str(result)[:2000]}` (truncate to fit context) to the messages list so the LLM can reason over the observation.