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

Beyond the readOnly/openWorld annotations, the description discloses return constituents (consistency check, revisions, source URL, retrieved_at, page SHA-256) and the three status values including the important not_found_in_checked_records case, which tells the agent that absence is scoped to checked records rather than proof of nonexistence. It also explains the session default ('omit for every session this service has read'). It stops short of describing coverage limits or freshness beyond retrieved_at.

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 core question and inputs are front-loaded, and the sentence listing return fields is compact. It is dense but nearly every clause carries information; 'Check the official page' is the only near-boilerplate line, though it usefully signals authority for the numbers.

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?

An output schema exists, annotations cover safety, and all parameters are documented, so the description only needs to add framing — which it does by explaining status semantics, provenance fields, and the session default. Nothing an agent needs to call this correctly appears to be missing.

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?

Schema coverage is 100%, so both parameters are already documented with accepted id/name forms and the dai N kai session convention. The description restates the exam forms (nurse/physician, Japanese or English) without adding syntax or disambiguation rules the schema lacks, so baseline 3 applies.

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 opens with a specific question form that states the resource precisely: applicant/examinee/passer counts and pass rates for Japanese national exams as published by MHLW. A verb+resource is clearly implied and the scope (all candidates and new graduates) is named, though it never distinguishes this lookup from the sibling exam_results_list.

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?

Usage is only implied: supply an exam identifier and optionally a session to get that exam's published results. There is no statement about when to prefer this over exam_results_list (which presumably enumerates available exams) or catalog, and no prerequisites beyond 'Check the official page.'

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