@@ -144,7 +144,7 @@ where $r_p$ indicates that the overall plan is reasonable, $r_1$ and $r_2$ indic
...
@@ -144,7 +144,7 @@ where $r_p$ indicates that the overall plan is reasonable, $r_1$ and $r_2$ indic
\subsubsection{Tool Use}
\subsubsection{Tool Use}
Tool use is another fundamental capability of LLM-based agents. Tools extend the agent beyond its internal parameters. They allow the agent to access external knowledge, perform accurate computation, and execute actions in external systems. Early studies show that LLMs can use tools through prompt-based reasoning-action patterns \citep{chang-etal:efficient,yao-etal:react}. ReAct is a representative example, where the model alternates between reasoning steps and tool-use actions \citep{yao-etal:react}. However, prompt-based tool use is often unstable. It also depends heavily on the capability of the model. Thus, SFT methods train LLMs on tool-use trajectories, so that the model can learn when and how to invoke tools from demonstrations \citep{komeili-etal:Internet,schick-etal:toolformer}. Still, SFT mainly teaches imitation. It cannot directly optimize whether the agent should use a tool, which tool it should select, or how to balance tool benefit with tool cost. RL provides a natural framework for efficient tool use. We can define rewards based on task success, tool-use correctness, tool-use completeness, and tool cost\citep{qian-etal:toolrl,singh-etal:agentic}.
Tool use is another fundamental capability of LLM-based agents. Tools extend the agent beyond its internal parameters. They allow the agent to access external knowledge, perform accurate computation, and execute actions in external systems. Early studies show that LLMs can use tools through prompt-based reasoning-action patterns \citep{chang-etal:efficient,yao-etal:react}. ReAct is a representative example, where the model alternates between reasoning steps and tool-use actions \citep{yao-etal:react}. However, prompt-based tool use is often unstable. It also depends heavily on the capability of the model. Thus, SFT methods train LLMs on tool-use trajectories, so that the model can learn when and how to invoke tools from demonstrations \citep{komeili-etal:Internet,schick-etal:toolformer}. Still, SFT mainly teaches imitation. It cannot directly optimize whether the agent should use a tool, which tool it should select, or how to balance tool benefit with tool cost. RL provides a natural framework for efficient tool use. We can define rewards based on task success, tool-use correctness, or tool-use completeness\citep{qian-etal:toolrl,singh-etal:agentic}.
