I can see this makes sense for simple { user_query -> search -> llm_answer } usage, where tool use is only a means to retrieve background info.

For complex real-world agent flows though, tool use is often the only thing that the LLM is expected to do. Like in a coding agent:

```

User: Develop a program to ...

Agent: Bash("touch main.py") > 0, ""

Agent: Edit("main.py", initial_patch) > 0, ""

Agent: Bash("python main.py") > 1, "SyntaxError: ..."

Agent: Edit("main.py", fix_patch) > 0, ""

Agent: Bash("python main.py") > 0, "OK"

Agent: FINISH

```

Here, tool selection (+ writing the arguments) is actually the whole job. It's also easy to see that if you omit even one of the tool use records in the middle, the agent wouldn't work at all.