Audit a live URL for motion accessibility (WCAG 2.2.2 / 2.3.3)

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

Annotations already declare readOnlyHint and openWorldHint. Description adds significant behavioral context: fetches HTML+linked stylesheets, scans CSS for four categories, returns specific JSON structure including badge and disclosures. Discloses network I/O explicitly, aligning with openWorldHint. No contradiction.

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?

Description is compact for the amount of detail, front-loading purpose and listing checks in a clear numbered list. Each sentence adds value. Slightly long but appropriate for the complexity.

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?

Despite no output schema, the description specifies the return structure ({ok, score, findings, summary, badge, disclosures, markdown}) and the condition for the badge. It covers limitations (runtime not audited) and network behavior. Complete for a single-parameter tool.

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 covers the single parameter (url) with 100% description. Description adds meaning by explaining the tool fetches the URL's HTML and linked stylesheets, implying the URL is the target page. This adds context beyond the schema's basic type and format.

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?

Description uses specific verb 'audit' with resource 'live URL', lists four concrete CSS checks, and explicitly distinguishes from runtime motion auditors by disclosing 'Runtime motion... not audited (V2)'. This differentiates from sibling tools (catalog, compile, stats, validate) clearly.

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?

Implicitly states use case for static motion accessibility checks on live URLs. Highlights that runtime motion is not covered, guiding agents to avoid this tool for JS-based motion. Could be more explicit about when to prefer sibling tools, but the limitation is clearly stated.

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