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

Beyond the annotations it discloses that only public published files are read, nothing is signed in or submitted, and that every call is billed ($0.01 via x402 USDC or card key, first 25 free, failures free, repeats not free). That adds auth, cost and non-idempotency context the readOnly/openWorld hints alone don't 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?

It is front-loaded with the score, the checked artifacts and the returned data, then behavior and pricing. It runs long in a single block and could be split, but nearly 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?

With no output schema, the description still enumerates the return contents (found/missing per artifact with URLs, robots.txt crawler verdicts, fix list), plus cost and read-only behavior. An agent has everything needed to decide and invoke 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% and the schema already explains that a domain or any URL on it is accepted and that only the origin is checked. The description reinforces this with an example URL but adds no new semantics 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 gives a concrete verb and object (score a website's AI-agent readiness 0-100) and enumerates exactly what is checked: llms.txt, sitemap, OpenAPI spec, MCP server card, A2A agent card and x402 discovery. That clearly separates it from adjacent siblings such as audit_website, seo_audit or pack_website_audit, though none of those siblings 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?

It states two concrete use cases ('audit your own site or vet a service before an agent relies on it') and supplies a worked call example with url=https://stripe.com. It stops short of stating when a sibling tool (e.g. seo_audit) would be the better choice.

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