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

Annotations already declare readOnly, idempotent, non-destructive and openWorld, so the safety bar is low. The description goes beyond them with the paid-call model ($0.005 USDC per successful call via x402 on Solana) and the parallel HTTPS endpoint, which materially affects how an agent should budget and invoke it.

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?

Tight and front-loaded: capability and output contract come first, then options, then pricing and the HTTP alternative. Every clause carries information, with only the URL reference being purely operational.

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 does supply the return shape: absolute URLs, classification, anchor text, rel and nofollow. Pricing, auth and the alternative transport are disclosed. It stops short of stating behavior for unresolvable base hrefs, redirects, or non-HTML pages, which for an openWeb fetch tool would be the final missing piece.

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%, with defaults and enum values documented per parameter, so the schema carries the load. The description only lists the option names and does not add format, unit, or interaction semantics beyond what the schema already says.

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 and resource: extract every link on a page, returned as absolute URLs with internal/external/other classification plus anchor text, rel and nofollow. The output shape is concrete enough that an agent can tell it apart from generic extraction siblings like web_to_text or url_markdown, though no sibling is named explicitly.

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 the resource name and output shape; there is no statement of when to choose this over url_markdown, html_to_markdown, web_to_text, or seo_audit. The listing of options (filter, dedupe, max_links) tells you how to tune it but not when to reach for it.

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