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. The description adds the requirement of a prior login, which is a behavioral trait. It does not describe pagination, result format, or any side effects beyond what annotations imply. Given annotations handle the read-only nature, the added login context earns a 3.

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 description is extremely concise: two sentences, the first stating a critical prerequisite, the second stating the action. It is front-loaded and contains no redundant or extraneous information. Every word earns its place.

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?

The description mentions the login prerequisite but omits details about pagination behavior, return structure, or how this tool relates to the init/page/result siblings for purchases. Given there is no output schema, an agent might not know what to expect from the call. However, the schema covers parameters, and the prerequisite is a key contextual element. Overall, it is adequate but with notable gaps.

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?

The input schema has 100% description coverage for all 7 parameters, including date formats and account_link_id guidance. The description adds no additional parameter semantics beyond what the schema already provides. Since the schema carries the full burden, the baseline of 3 is appropriate.

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 clearly states it searches KB Biz Card purchases rows, which is a specific verb+resource. However, it does not differentiate this from sibling tools like kb_biz_card__approvals__search or kb_biz_card__payments__search, leaving ambiguity about the exact distinction between purchase, approval, and payment data. The title provides the Korean equivalent but not additional clarification.

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?

It explicitly states a prerequisite: a prior kb_biz_card__session__login call with the same account_link_id. This is useful. However, it gives no guidance on when to use this tool versus the sibling search tools for approvals or payments, nor does it mention any conditions under which this tool should not be used.

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