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

Annotations already establish readOnlyHint and openWorldHint, so the description adds real value on top: it declares the extraction is fact-only, that missing fields are reported back, and that ratings/reviews/prices are never fabricated. That anti-hallucination contract is exactly the kind of behavior an agent needs and cannot get from annotations.

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?

Front-loaded with the deliverable, then the field list, then the guardrails — the strongest behavioral claim ('never invents') lands last but is memorable. It's dense with no filler, though the semicolon-chained clauses read a bit compressed.

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, so the description carries the return-value burden — and it does, saying the output is JSON-LD plus a list of fields that could not be found. Combined with the fact-only guarantee, an agent knows what to expect; only the exact envelope shape is unspecified.

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 75%, so most parameters are documented in the schema itself, and the description adds nothing about url vs html precedence, optional name, or how `type` overrides detection. It mentions the supported entity types, which loosely maps to the `type` parameter, but no format or defaulting detail beyond what the schema 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 concrete deliverable: JSON-LD structured data generated for a page, enumerating the entity types and fields it covers. It's specific enough that an agent knows exactly what comes back, though it never names a sibling to distinguish itself from (e.g. review_page or audit_search).

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 — the description makes clear you supply a page and get markup, but there is no explicit 'use this when…' vs an alternative, and no stated prerequisites beyond 'public URL' from the schema. An agent can infer the context but is not guided between this and any related auditing tools.

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