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 login prerequisite, which is a useful behavioral context not in annotations. It does not describe pagination, result format, or any side effects, but given the annotation coverage, the description's contribution is adequate.

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 short sentences. The critical prerequisite is front-loaded. There is no fluff or redundancy. It is efficiently structured for a tool with a simple purpose.

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?

Given the rich sibling context (init, search, page, result), the description does not explain how this tool fits into the overall workflow. It does not mention that it likely gathers all rows after a search, nor does it specify any ordering or interaction with other tools beyond login. This is a significant gap for an agent trying to sequence calls correctly.

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 coverage is 100%, so all parameters are described in the schema. The description adds no extra parameter-specific meaning; it only references account_link_id in the context of the login prerequisite, which is already explained in the schema. Baseline 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?

The description states a clear verb ('Collect') and resource ('KB Biz Card purchases result rows'). It is specific about the outcome, but it does not explicitly distinguish itself from sibling tools like kb_biz_card__purchases__search or __page. The name implies a result-collection role, and the description aligns with that, so it is clear but not fully differentiated.

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 explicitly requires a prior login call with the same account_link_id, which is a valuable prerequisite. However, it does not explain when to use this tool versus the sibling init/page/search tools, nor does it describe the expected flow (e.g., after a search). It provides a prerequisite but no guidance on alternatives.

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