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

Annotations already declare readOnlyHint and openWorldHint, so the safety profile is covered. The description adds real value: rendering is conditional on Chromium availability, viewports are 1280×800 and 390×844, screenshots are saved, and output is scores plus fails-with-evidence-and-fix. It does not say what happens when Chromium is absent or how the kit is resolved, but with annotations present this is acceptable.

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 tool's purpose and then the check categories, ending with what it returns. No wasted sentences, though the jargon ('kit drift', 'the Look fails', 'AEO, GEO') will not parse for every agent.

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?

No output schema exists, and the description compensates by stating the return shape (scores, fails first, evidence and fix). For a 7-param, nested-schema tool it is largely complete, with the main gap being how the three input sources (url/html/file) and kit resolution interact.

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 coverage is 86%, so the schema already documents most parameters, setting the baseline at 3. The description's mention of viewports and screenshots lightly illuminates render/images/out_dir but adds no precedence rules for url vs. html or kit sourcing beyond what the nested schema already states.

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?

Opens with a specific verb-plus-resource ('The all-in-one check for a built page') and enumerates the check categories: look/kit drift, SEO, AEO, GEO, and a rendered accessibility pass. It is clearly broader than the audit_search/audit_slop siblings, though it never names them to make the boundary explicit.

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 by 'all-in-one check for a built page' and the conditional note about Chromium availability. There is no explicit when-to-use vs. audit_slop or audit_search, and no guidance on choosing url vs. html vs. file input.

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