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

Annotations already declare readOnly, idempotent, openWorld and non-destructive behavior, so the safety profile is covered. The description adds real value beyond that: it discloses the non-invasive probing stance, a concrete price ($0.005 USDC per successful call, x402/Solana), and an alternate HTTPS endpoint, though it says nothing about rate limits, failure modes, or what a partial/bot-blocked response looks like.

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 output inventory is front-loaded and dense with no filler; the payment and endpoint details are tacked on the end but are short. Slightly crammed into one long sentence, but every clause carries information.

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 enumerating the returned signal categories (CMS, frameworks, CDNs, analytics, payments, meta, script/stylesheet samples). Combined with payment terms and the alternate endpoint, an agent has everything needed to call it and anticipate results.

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?

With a single required parameter at 100% schema coverage, the schema already documents the url field fully. The description only reinforces that the target must be public and http(s), adding minimal semantics beyond the schema, which matches the baseline for high 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 names a specific verb-and-resource pair (technology fingerprint from public HTML/headers) and enumerates the concrete detections—CMS, frameworks, CDNs, analytics, payments, generator meta. That makes it clearly distinct from siblings like headers_audit, http_probe, or seo_audit in practice, though it never explicitly names an alternative to differentiate itself.

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?

It establishes scope with 'No invasive probing' and offers an HTTP fallback endpoint, but gives no explicit when-to-use guidance versus closely related sibling tools such as headers_audit, http_probe, or seo_audit. Usage is implied by the output inventory rather than stated as a routing rule.

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