Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

With no annotations, the description carries the full burden, but it only lists content categories and gives no operational traits: no read-only/write indication, no mention of side effects, and no return shape. The '口' metaphor makes it ambiguous whether invocation observes gaps or declares them.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Is the description appropriately sized, front-loaded, and free of redundancy?

The description is brief and front-loads the three gap types before the purpose statement. The poetic ending is not strictly necessary but does no real harm; no word is inflated.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

The tool is simple (one optional boolean, no output schema), so the description is minimally usable, but it does not state what a call returns, how include_resolved affects results, or how this tool relates to unconfirmed/status siblings. It is adequate as a hint, not complete enough for confident invocation.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

The schema alone documents include_resolved with a clear Japanese description, and schema coverage is 100%, so baseline 3 applies. The tool description adds nothing about this parameter or how including resolved gaps changes behavior.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Does the description clearly state what the tool does and how it differs from similar tools?

The description names concrete categories (known_gaps, attempts, findings) and states the goal of making absence expressible, so it is not a tautology. However, it never uses a concrete verb such as list/get/retrieve; the metaphorical '口' leaves it unclear whether this tool returns gaps, records gaps, or reports a status.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Does the description explain when to use this tool, when not to, or what alternatives exist?

It implies a use case: use this when you need to know or assert what is missing ('何が無いかを、無いと言えるようにするため'). It gives no explicit when-not or alternative guidance, and does not contrast with siblings such as jhnrd_unconfirmed or jhnrd_status.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.