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

With no annotations, the description carries full disclosure burden, and it does add one real behavioral fact: besides the checklist it also returns site-wide reduced-motion CSS. It does not say whether output is static text, whether it inspects a URL, or anything about read-only/risk profile, though the zero-param nature limits risk.

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?

A single dense sentence, front-loaded with the content type and then the covered standards, with no filler prose. The '[網頁動畫工具箱]' bracket prefix is mild overhead that does not aid selection.

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 parameterless, guidance-style tool with no output schema, listing the standards covered and the bundled reduced-motion CSS is enough for an agent to know the shape of the result. It could state whether the CSS is template/scaffold versus site-specific, but the essentials are present.

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 takes zero parameters, so there is no parameter semantics to document; per the baseline that yields a 4. The description correctly adds no invented arguments.

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 names a specific resource — an accessibility and performance checklist for web animations — and enumerates the exact criteria covered (WCAG 2.2.2, 2.3.1, 2.3.3, prefers-reduced-motion, CLS, LCP), which clearly separates it from the code-generating siblings (generate_easing, generate_keyframes). It is a content-label rather than a verb+object statement, but an agent can tell what it produces.

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?

Usage is only implied: the checklist framing suggests you call it when auditing web animations for a11y/perf, but there is no explicit when-to-use, prerequisite, or named alternative among the motion__ siblings. Adequate but leaves routing to inference.

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