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

Annotations already declare readOnlyHint=true and destructiveHint=false, covering the safety profile. The description adds no extra behavioral context beyond the basic purpose, such as what happens if no session exists or what fields are returned. With annotations covering the safety aspects, a 3 is appropriate as the description contributes minimal additional transparency.

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 a single concise sentence that clearly states the action and target. There is no unnecessary text, and the core purpose is front-loaded. It is optimally brief for the information conveyed.

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 simple read-only retrieval tool with one optional parameter and full schema coverage, the description is largely sufficient. However, it could mention the implicit requirement of an active session or clarify that it returns the current user's details, which would improve completeness. Given the annotations cover safety, this minor gap keeps it at a 4 rather than a 5.

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 schema description coverage is 100% for the single optional parameter, so the schema already documents its meaning and usage. The tool description does not add any further explanation about the parameter's role or multi-institution distinctions. Following the baseline for high coverage, this is a 3.

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 specific verb ('Retrieve') and a clear resource ('logged-in user info from Hometax'). This distinguishes it from sibling tools like hometax__session__login (which performs login) and other Hometax data retrieval tools. The purpose is unambiguous and instantly understandable.

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 provides no guidance on when to use this tool versus alternatives. It does not mention prerequisites such as an active session, nor does it explain when the optional account_link_id would be needed. The context is implied by the name and description, but explicit usage conditions are absent.

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