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

Annotations already declare readOnly, idempotent, non-destructive and openWorld, so the safety profile is covered. The description adds genuinely new behavioral context: results are ranked with a confidence score, ambiguity is expected ('Samsung Electronics' matches four), and the data comes from two named registries (DART, Public Procurement Service) — which explains coverage limits an agent would otherwise not anticipate.

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?

Front-loads the core purpose, then the usage condition, then the return shape and sources. The Samsung example is the one apparent indulgence but it concretely demonstrates the ambiguity the tool exists to resolve, so it earns its place. No filler.

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?

With no output schema, the description carries the burden of describing return values and does so (ranked candidates, confidence score, discriminating evidence such as registration status, tax type, region). It also discloses data provenance, which is the remaining thing an agent needs to judge result trustworthiness.

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, including the English/Korean name forms that the description repeats. The description's note that a name can match several distinct companies implicitly justifies the `limit` parameter, but it never discusses `limit` or its default directly, so the added meaning is indirect.

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+resource (find a Korean company by name) and immediately scopes it against the rest of the toolset by noting it applies when the 10-digit registration number is unknown — 'the number every other tool here needs.' An agent can distinguish it from verify_korean_business and check_korean_business_status without opening any schema.

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?

Gives an explicit selection condition (you do not know the registration number) plus the implied inverse: the sibling tools are the ones that need the number. It also sets expectations for the ambiguous case and names the upstream sources, so the agent knows when this is the right entry point.

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