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

Goes well beyond the annotations by disclosing concrete rate limits (10/minute, 100/day per IP, per account when signed in), that nothing is persisted ('Saves no report'), and that the check is performed live against a public site. These are exactly the operational facts an agent needs before calling and none contradict readOnlyHint/idempotentHint/openWorldHint.

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?

Two dense sentences with no filler; access terms come first and the alternative follows. It is slightly overloaded with semicolon-separated clauses, 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?

With no output schema, the description compensates by enumerating the returned fields (score, grade, category scores, robots.txt crawler allowances, llms.txt presence, top 3 fixes). Coverage details, access model, rate limits and the escalation path are all present, so nothing needed to call it correctly is missing.

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 description coverage is 100% and already gives the format example ('https://example.com or example.com'), so the description can only add the constraint that the target must be public — a small increment. Baseline 3 is appropriate since the schema does the heavy lifting.

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 ('Checks a public website live') plus the exact artifact returned ('0–100 AI search readiness score, grade, category scores...'). It also names the distinguishing sibling, audit_url, so an agent can separate the free quick check from the Pro report without inspecting either schema.

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?

Clearly frames itself as the free, no-sign-in entry point and explicitly routes to audit_url (Pro) for the full failing-check list with a shareable report and badge. The 'when to use' is implied by cost/scope rather than stated as an explicit condition, keeping it just 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.