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

Beyond the readOnlyHint annotation, the description adds critical behavioral detail: the default 3-day window, the misleading empty-result behavior, the one-calendar-month limit, and the institution returning an empty list instead of an error for long periods. This is exactly the kind of non-obvious runtime behavior an agent needs.

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 dense but every sentence earns its place. It front-loads the mandatory prerequisite, then states purpose, read-only nature, date defaults, and edge-case behavior in a structured, scannable way.

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 read-only list operation with no output schema, the description covers prerequisites, defaults, pagination-relevant date constraints, failure semantics, and the key returned identifiers. An agent has what it needs to call this tool correctly and interpret empty results.

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 the baseline is 3. The description adds value beyond the schema by explaining that both dates must be sent together, that omitting them means a 3-day window, and that periods longer than one month are refused and should be split into monthly calls.

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 and resource: 'List certificate applications already filed at Hometax with their receipt ids (cvaId, rcatNo).' It clearly distinguishes this read/list operation from sibling apply/download tools by emphasizing 'already filed.'

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 requires a prior hometax__session__login call with the same account_link_id, giving a clear precondition. It also provides concrete guidance on date usage: 'Send both dates or neither' and how to handle empty results by widening the period. It does not explicitly name alternatives, but the conditions are clear.

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