Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?
For a 0-param, no-output-schema tool, the description covers the return values (every scene, current program and preview scene names) and is sufficient. Minor gap: it doesn't specify 'current scene collection' context, but this is inferable from the sibling tools. Given the minimal complexity, it is nearly complete.
Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.