Audit an HTML document

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

Annotations already declare readOnlyHint=true, idempotentHint=true, and destructiveHint=false, so the agent knows this is a safe, read-only operation. The description adds 'isolated headless browser' and 'Read-only' which align with and reinforce the annotations. No contradictions. The description provides modest additional context beyond the annotations.

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 sentences with no redundant or filler content. The first sentence clearly states the action and outcome, and the second provides usage guidance and a read-only note. Every part earns its place, making it highly efficient.

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 tool with 7 parameters and no output schema, the description covers the core purpose, usage context, and safety (read-only). It mentions the output type (WCAG findings, evidence, corrections) at a high level. However, it does not explain how parameters like standard or maxIssues influence behavior, though the schema descriptions handle those details. The description is sufficiently complete for an agent to use the tool effectively.

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 each parameter already has a description in the input schema. The tool description does not add specific parameter-level details, but it does describe the output (WCAG findings, evidence, corrections), which indirectly informs parameter usage. Baseline 3 is appropriate given full schema coverage.

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 a specific verb ('Render') and resource ('supplied HTML') with a clear outcome ('return WCAG findings plus evidence and suggested corrections'). It also distinguishes from sibling tools like audit_url and audit_file by stating 'Use for generated UI before it is hosted', making the purpose 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 description explicitly says 'Use for generated UI before it is hosted', which provides clear context for when to use this tool. While it does not explicitly list alternatives or when not to use, the sibling tool names (audit_url, audit_file) imply the distinction, and the guidance is sufficient for an agent to select this over siblings.

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