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

Goes well beyond the annotations: it discloses the payment model ($1.00 per call over the Machine Payments Protocol or a prepaid credit via Bearer auth), that the page is validated before payment is taken, and that a failed check is not charged. Annotations only cover read-only/open-world/idempotent, so these cost and billing semantics are genuinely additive.

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?

A single dense paragraph with no filler sentences; each clause carries real information (crawler rules, directives, site signals, scoring, billing). It is slightly front-loaded on payment terms before the core purpose, which weakens the leading position.

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 carries the return burden and does so: a 0-100 score against a published rubric plus prioritized findings, each with observation, rationale, and fix. Scope, payment, and return format are all present.

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 50% and the description adds nothing about parameters. The `idempotencyKey` property has no description in either the schema or the description, so its role in retry/payment safety is entirely undocumented; the `url` example comes from the schema, not this text.

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: it audits one public page for AI/search crawler visibility, listing exactly what is inspected (robots.txt rules, directives, meta, JSON-LD, server-rendered text, site signals). This is unmistakably distinct from the payment/listing siblings.

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?

Scoping is clear: it works on 'one public page from public fetches only' and explicitly disclaims any ranking/traffic/citation outcome, so the agent knows the boundaries of the result. It does not name alternative tools or the exact condition for choosing a different sibling, so it stops short of a 5.

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