Why langgraph ReAct agent does not have a 'Thought' step?

[fengsp]

Example Code
from langgraph.prebuilt import create_react_agent

Description
When this agent runs, it never show any 'Thought' step

[hwchase17]

it is using function calling directly, instead of the thought/action/observation prompting style

[hinthornw]

To add to this, some models like Claude 3 perform function calling with a "thought" step built-in, while others (like OpenAI) do not. It's a bit provider-dependent right now

[itxabdullahbinasad]

@hwchase17 Is there a way we can add it in the prompt with adding the variables of tool names and tool in the prompt and just telling it in prompt but then should i give this prompt to the function tool calling agent or langgraphs prebuilt create react agent in the message modifier

[fengsp]

I tried with Qwen models and just add "Think step by step" to the prompt，the AI message will return tool_calls also the Thought content.

[hwchase17]

yes, you could definitely add this in - either as a field in the tool calls or by telling it think before answering (models like GPT-4o can generate text before a tool call)

[kashyap-aditya]

Can we get some documentation on how to get the Thought/Observation/Action pair to work along with tool calling?

Are you suggesting that we add Thought/Observation as input parameters to each tool?

[luizzappa]

With OpenAI, tools are called without "thought". The workaround I did was to add a "reason" field to each available tool in which LLM must fill in the reason for calling that function, thus forcing the intermediate thoughts to be recorded. But it is worth testing whether this improves performance in your use case or not.

[kashyap-aditya]

I am not sure it is accurate to call it a react agent when there is no Thought/Observation/Action pair being output.

What makes it a react agent and how is it different from just a tool calling agent?