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

Annotations already declare readOnlyHint and idempotentHint, so safety is covered. The description adds context about content source (official guide) and that it reflects current calculation rules, but no further behavioral caveats (e.g., data freshness or scope limits) are disclosed.

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 two well-structured sentences: the first front-loads the main purpose and enumerates the covered rules, the second references the source and lists example questions. Every sentence earns its place; no redundancy.

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?

With an empty input schema, an output schema available, and read-only annotations, the description thoroughly explains the tool's domain, content, and intended use cases. It enables an agent to select this tool appropriately among siblings like tariff lookup or tax estimation.

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 tool has zero parameters, so the baseline is 4. There are no parameter details to provide, and the description does not need to compensate for any schema gaps.

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 tool retrieves Taiwan express import simplified declaration rules, listing specific content (C1/C2/C3, EZ WAY, NT$2000 exemption, 6-times limit, 5% tax). It also gives example user questions to distinguish it from sibling tools like tax estimation.

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 includes suitable query examples (e.g., 'how much tax to pay', 'what is simplified declaration'), providing strong usage guidance. It does not explicitly state when not to use or name alternatives, so it falls short of a 5.

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