ReAct (Reasoning + Acting) interleaves thought and action: model reasons (Thought), calls a tool (Action), observes the result (Observation), repeats until done.

ReAct (Reasoning + Acting) interleaves thought and action: model reasons (Thought), calls a tool (Action), observes the result (Observation), repeats until done. In Strands: the agent loop manages this cycle — model generates a response, if it includes a tool call, Strands executes it and feeds the result back, until the model outputs a final response with no tool call.