Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?
Given 4 parameters with 0% schema coverage, no output schema, no annotations, and a rich family of text-related sibling tools, the description is under-specified. The return-object shape is shown but fields (tag, match, w, h) are unexplained, and matching semantics (partial vs exact, case sensitivity, visible vs source text) are unclear. The example conveys the core idea but leaves too much to infer for an agent to use this reliably.
Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.