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

Annotations already declare readOnlyHint, idempotentHint, destructiveHint=false and openWorldHint=false, so safety is covered. The description adds genuinely useful non-annotation context: the values are NHIS-published yearly-refreshed evaluation results (data provenance and staleness) and an explicit instruction not to fabricate missing values. It does not describe pagination or result size.

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 content is front-loaded and each sentence carries information, but the entire text is duplicated verbatim in Korean and English, roughly doubling the length with zero additional semantic payload. It is adequate rather than tight.

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?

There is no output schema, and the description compensates reasonably by describing what the result contains (institution counts by region, benefit-type counts, embedded region page URL). Combined with the yearly-refresh provenance note, an agent has enough to call and interpret it, though result shape details remain thin.

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 description coverage is 100%, so both parameters are already documented in the schema, including that omitting sido yields province totals. The description's restatement of the gugun-plus-sido behavior adds no syntax or format detail beyond the schema, so the baseline of 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?

States a specific resource and measure: institution counts by province/district, plus benefit-type breakdown when a district is supplied, and mentions the region page URL is included in the result. It is distinguishable from get_stats and search_institutions, though it never names or contrasts with those siblings.

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?

The description gives a conditional behavior ('if you pass gugun you get benefit-type counts' and 'never guess missing values, point to the url or contact'), but it does not say when to prefer this over get_stats or search_institutions, nor any prerequisites or exclusions. Usage is implied rather than stated.

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