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

No annotations are provided, so the description carries the full behavioral burden. It does disclose a genuinely useful trait absent from structured data — the $0.01 per-call cost — but says nothing about auth requirements, whether extraction is live or cached, or what happens on pages with no structured data.

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 short sentences with zero filler; the capability is front-loaded and the pricing note follows. Every sentence earns its place.

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 one trivial parameter, no nested objects, and no output schema, little description is strictly required, and the return format is at least implied by the listed formats. Still missing is any indication of result shape or how the three formats combine in one response.

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 0%, but there is only one parameter (`url`) whose semantics are largely self-evident from the name and from 'from a page'. The description adds no format detail (absolute URL, redirects, JS-rendered pages), so it neither compensates for nor worsens the gap — a baseline 3.

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 (Extract) and enumerates the exact resource formats it targets (schema.org JSON-LD, microdata, OpenGraph), so the agent knows precisely what comes back. It does not, however, distinguish itself from the sibling page_meta, which plausibly overlaps on OpenGraph/meta extraction.

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?

There is no guidance on when to choose this over page_meta, batch_meta, or readable_text, nor any exclusions. The agent must infer selection purely from the resource names in the sibling list.

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