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

Adds behavior beyond the annotations: the exact credit cost (1, or 5 with render=true) and the guarantee that a failed call is free, plus that render means the audit happens post-JS execution. Annotations already declare readOnly/openWorld, so this is solid added context, though it does not describe latency or result freshness.

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?

Two sentences, front-loaded with the audit scope, followed by the cost/pricing clause. No filler; every phrase carries information the agent needs.

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 no output schema, the description compensates by enumerating the audited fields and mentioning the score, and it covers cost and failure behavior. An agent has enough to decide and call correctly.

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 100%, so the baseline is 3; the description earns an extra point by quantifying the render cost (5 credits) and restating the post-JavaScript semantics in cost terms, which the schema only vaguely calls 'costs more'.

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?

States a specific verb (audit) and resource (one public page) and enumerates exactly what is examined: title, description, canonical, robots/indexing directives, headings, links, images, structured data, plus a score. Clearly distinct from scrape/search/sitemap siblings which are not audits.

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?

Scopes usage to a single public page and gives the key selection criterion for the render flag (audit after JavaScript runs). It does not explicitly say when to prefer this over sibling tools like scrape or sitemap, so it falls short of full alternative routing.

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