Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?
For a simple 0-parameter list tool, the description is adequate: it identifies the output (clients with their context) and the intended use case. It doesn't specify the return format (e.g., array of objects), but that is often implied. With no output schema, a bit more detail about the response could improve completeness, but the current level is acceptable for the simplicity of the tool.
Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.