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

Annotations already indicate read-only, idempotent, non-destructive behavior, so the safety profile is clear. The description adds context about redirect and response provenance, plus privacy-safe, publisher-asserted Organization facts with field evidence, which goes beyond the annotations without contradicting them.

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?

The description is a single dense sentence that front-loads the core purpose and then lists many outputs. It is efficient but somewhat run-on; breaking the metadata list into separate clauses would improve readability without adding length.

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?

The tool has an output schema, so return values are documented elsewhere. The description covers the main metadata categories and adds provenance details, making it complete for a read-only single-URL tool. No major gaps are 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 description coverage is 0%, but the single 'url' parameter is self-explanatory. The description reinforces that it must be a 'public URL', adding a real constraint not present in the bare schema. It also implies the URL should be a single URL, not a batch.

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 starts with 'Extract webpage metadata from one public URL', using a specific verb and resource. It enumerates a detailed list of metadata types (title, description, canonical, headings, hreflang, icons, feeds, Open Graph, Twitter Cards, JSON-LD), which clearly distinguishes it from sibling extractors like web.extract or web.links.

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?

The scope is implied to be 'one public URL', but the description does not explicitly state when to use this tool versus alternatives like web.extract or web.seo-audit. No exclusions or alternative suggestions are provided.

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