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

No annotations are provided, so the description carries the full burden of behavioral disclosure. It only states the audit purpose, but does not disclose what the tool returns (e.g., issue list, pass/fail result), whether any side effects occur, or if it requires authentication. 'Audit' implies read-only but is insufficient for an agent to anticipate the output.

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 a single, front-loaded sentence with no filler. Every word ('Audit', 'raw HTML', 'WCAG 2.1 AA issues') adds distinct value. It is appropriately concise.

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 only one parameter and no output schema, the description is minimally viable: it states the tool's core function and input. However, the absence of annotations and output details leaves gaps about expected results and edge cases, so it is not fully complete for an agent invoking the 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 description coverage is 0%, so the description must compensate for the 'html' parameter. The description's 'raw HTML' directly explains the parameter's meaning, but it lacks extra context like expected format (full document vs. fragment) or encoding constraints. This is a basic but adequate semantic contribution.

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 uses the specific verb 'Audit' and the resource 'raw HTML' with the standard 'WCAG 2.1 AA issues', clearly distinguishing it from siblings like a11y_audit_url (which audits URLs) and a11y_contrast/a11y_headings (which focus on specific aspects). The purpose is unambiguous.

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 phrase 'raw HTML' indicates the tool is for direct HTML input, implying it should be used when you have HTML code rather than a URL. While it doesn't explicitly name alternatives or exclusions, the context is clear enough for an agent to infer appropriate usage compared to sibling tools.

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