Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?
The tool is simple with no parameters and no output schema, but given the lack of annotations, the description should provide more behavioral context (e.g., whether it clears the internal buffer only, whether it deletes files). The word "buffer" implies non-destructive-to-files, but this is not explicit, leaving some ambiguity.
Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.