Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?
For a one-parameter, read-only tool with an output schema, the description covers how to identify the destination, what to expect in the result, and when to prefer it over destination_overview. The only light gap is that 'live mcp_endpoint' is domain jargon, but the output schema presumably defines it.
Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.