Side Effects and Costs Introduced by Tool Use

Characterize the side effects and costs that tool use introduces for web agents, including potential increases in token usage, action overhead, and other execution inefficiencies compared with direct low-level browser interaction.

Background

Although tools can replace long sequences of low-level actions, little is rigorously known about their potential hidden costs, such as larger prompts, retrieval overhead from large tool libraries, or error-recovery effort from brittle tool calls.

A systematic characterization of these side effects is necessary to weigh the benefits of tool use against its potential efficiency and reliability trade-offs in practical web-agent deployments.