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

Goes well beyond the destructiveHint/readOnlyHint annotations by naming the concrete side effect (an application filed with the NTS and a receipt record cvaId + rcatNo created), stating that no cancel action exists, and disclosing a per-call token cost. This is exactly the extra context the annotations cannot convey.

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?

Front-loaded with the hard prerequisite and the irreversibility warning, then the confirm flow, then cost. Every sentence carries information, though the confirm flow restates what the schema already documents for the confirm parameter.

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 an irreversible mutation with no output schema and no required parameters, the description covers the prerequisite, the side effects, the absence of undo, and the approval protocol. It stops short of describing what the preview actually contains, which an agent must show to the user, so it is not fully complete.

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 description coverage is 100%, so the nine form fields are already fully documented in the schema. The description adds the confirm-flag protocol context, but that is also spelled out in the confirm parameter's own description, so the marginal gain is small. 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?

States a specific verb and resource: 'Apply for National Tax Payment Certificate from Hometax.' An agent can immediately tell this is a certificate application, not a lookup or download. However, it never distinguishes itself from the near-identical sibling hometax__certificate__apply__tax_payment_record, which a naive reader could easily confuse with this one.

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?

Explicitly gives the precondition (prior hometax__session__login with the same account_link_id) and a mandatory two-call protocol: preview without confirm, show the user, then retry with confirm=true, and never auto-confirm. It does not say when to choose this certificate type over the other hometax certificate-apply siblings, so the 'vs alternatives' half of the guidance is missing.

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