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

Beyond the annotations (readOnlyHint, openWorldHint), it discloses the exact cost ($0.03 USDC via x402), the fact that calling first returns the HTTP request and payment requirements rather than data, and that an x402 client is needed to complete payment. This two-step payment behavior is critical context the annotations cannot convey.

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?

Front-loaded with the cost and payment model, then the audit scope, then the payment mechanics. Dense but every clause adds information about what is returned or how to invoke it; no filler.

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 usefully enumerates the returned fields and explains the payment flow, which is the key non-obvious behavior. The only meaningful omission is the format/validation expectations for the url argument.

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 0%, so the description carries the burden, and it never describes the single 'url' parameter's expected format or examples. The parameter name is self-evident in the context of a page audit, so the gap is minor, but no meaning is added beyond the schema.

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 states a specific verb+resource ('one-call page audit') and enumerates the exact scope: HTTP status, redirects, latency, meta tags, Open Graph, JSON-LD, headings, word count, plus agent-friendliness checks. This clearly differentiates it as a comprehensive audit, though it never names the siblings it overlaps with (page_meta, robots_check, page_markdown).

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 implied by 'for agents' and the enumerated outputs, and the payment flow tells the agent this is a paid tool that must be paid before data is returned. However, there is no explicit when-to-use guidance and no routing to cheaper siblings like page_meta or robots_check that cover subsets of the same data.

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