Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?
Given the simple single-parameter input, no output schema, and straightforward read behavior, the description provides enough information for an agent to call the tool. It explains the core behavior, input format, and cost. It could add potential failure modes (e.g., password-protected pages), but not essential for basic use.
Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.