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

With no annotations, the description does real work: it names the data source (시·군 및 대전시 공개 가맹점 목록), discloses the coverage limitation (only regions with lists), and describes the fallback behavior for unsupported regions. It stops short of describing the shape or ordering of returned results.

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?

Three short sentences, front-loaded with the core purpose, then data source, then coverage caveat. No filler, though the coverage caveat could be folded tighter.

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?

For a 3-parameter read tool with no annotations and no output schema, the description covers purpose, source, and the important limitation that some regions will not return results. Only the returned fields/ordering are unaddressed, a minor gap given the schema carries the parameters.

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 region, query, and limit are already fully documented with examples and semantics. The description only restates that lookup is by region and search term, adding no syntax or edge-case detail beyond the schema.

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 verb and resource ('지역화폐를 받는 가맹점 ... 찾습니다') plus the scope of business types and the two lookup keys (region, query). The mention that it only answers regions with published lists, and redirects otherwise, clearly separates it from list_regions.

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 context is clear: use it to find local-currency merchants given a region and optional search term. The fallback sentence ('목록이 있는 지역을 알려 줍니다') implicitly hands off discovery to list_regions, but no sibling is named explicitly and there are no stated exclusions.

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