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

Annotations already declare readOnlyHint=true and destructiveHint=false, so the safety profile is covered, but the description adds valuable context: the auth requirement, the explicit non-submission/non-storage guarantee, and the fields returned despite no output schema.

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 tightly scoped sentences with the prerequisite front-loaded and no filler. The read-only sentence mildly overlaps the annotation but still earns its place as an explicit guarantee for a lookup tied to a save workflow.

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 compensates by naming the returned fields, and it covers the auth prerequisite and side-effect profile. Complete enough to invoke correctly, missing only a pointer to the alternative sibling tools for the broader workflow.

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 the schema already documents all three parameters including the account_link_id auto-resolve behavior. The description only restates that lookup uses name and RRN, adding no syntax or format 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 (조회/lookup) with the resource (가입자/subscriber) and the exact lookup keys and return payload (rrkey, 대표자 여부, per-insurance 자격취득일·상실일). It is easily distinguished from siblings like los_member_lookup and acqs_save.

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 clearly frames usage ('자격취득 신고서를 쓰기 전에') and states the hard prerequisite of a prior session login with the same account_link_id. It stops short of naming the alternative tool (e.g., acqs_precheck or acqs_save) for a different step.

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