Check caching & delivery headers

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

Annotations already declare readOnlyHint=true, and the description adds meaningful context by listing exactly which headers are inspected (Cache-Control, content-encoding, ETag/Last-Modified) and the HTML document size. It does not detail network fetch behavior or failure modes, but that is partially covered by openWorldHint and the read-only nature.

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 one concise sentence, immediately starting with the action verb 'Inspect' and enumerating specific headers without any verbose or redundant phrasing. Every word contributes to understanding the tool's purpose and scope.

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?

For a simple, one-parameter read-only tool with clear annotations and a detailed list of what is inspected, the description is fairly complete. It does not specify the return format, but with no output schema and the tool's straightforward nature, this is a minor gap.

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?

The schema provides a 100% descriptive coverage for the single 'url' parameter with a clear example ('Page URL to check, e.g. https://example.com'). The description does not add extra parameter semantics beyond what the schema already includes, so the baseline 3 applies.

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 clearly states a specific verb ('Inspect') and resource ('Cache-Control, content-encoding, ETag/Last-Modified headers and HTML document size'), which precisely defines the tool's function. It also distinguishes itself from sibling audit tools by focusing on caching and delivery headers rather than general SEO or rendering checks.

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 description implies usage for evaluating caching headers and speed optimization opportunities, but it provides no explicit when-to-use or when-not-to-use guidance, nor does it reference alternatives among the sibling tools. The context is present but not clarified with exclusions.

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