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

Annotations only declare destructiveHint=true and readOnlyHint=false; the description adds that the action is irreversible, files a real application with the NTS, creates a receipt record (cvaId + rcatNo), and has no cancel action. It also instructs the agent to never set confirm=true autonomously, which is critical behavioral context. This is exactly the kind of side-effect disclosure annotations alone do not provide.

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 compact and front-loaded: prerequisite, action, irreversibility, then confirm workflow. The all-caps warnings draw attention to critical constraints without becoming noise. No sentence is filler.

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 10-parameter irreversible external action, the description covers the dependency, the irreversibility, the receipt outcome, and the exact confirm flow. It does not describe the preview response shape or how to route to sibling download/apply tools, but the schema covers parameter semantics. It is sufficient for correct invocation in most cases.

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%, and the input schema already documents every parameter, including confirm's two-phase semantics, cert_template enums and defaults, optional account_link_id, and use_company_tin default. The description itself adds no additional parameter-level details beyond what the schema already provides. Baseline 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 the action ('Apply for a certificate using the logged-in taxpayer's own details') and the resource, making it more than a tautology. It does not explicitly distinguish this generic auto tool from sibling tools like hometax__certificate__apply__business_registration or hometax__certificate__apply_with_template, so agents must infer the difference from the name. Clear, but missing explicit sibling differentiation.

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 gives explicit execution guidance: a prior hometax__session__login with the same account_link_id is required, and the preview-then-confirm=true retry workflow is spelled out. It does not, however, state when to choose this tool over the sibling certificate apply tools, so the 'when not to use' side is missing. This is clear context without explicit alternatives.

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