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

With no annotations provided, the description carries the behavioral disclosure burden. It adds a meaningful privacy trait: 'Page content is not stored.' It does not mention network behavior, redirects, or that many input fields are discarded, but it does establish a read-only, non-persistent profile.

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 no filler. The core function is front-loaded and the privacy note earns its place as a behavioral clarification.

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?

Despite full schema descriptions, the tool has 9 parameters, 0 required parameters, no output schema, and no annotations. The description does not explain why so many unrelated parameters exist, which parameter should actually be supplied, or what the response structure looks like. This is incomplete for safe autonomous invocation.

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 input schema already has 100% description coverage, so the baseline is 3. The description itself adds no parameter-level guidance beyond implying the url parameter is the relevant input, while the schema descriptions explain the other parameters.

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 states a clear action and resource: 'Return host, scheme, and HTTP status for a URL.' It does not explicitly compare against siblings like normalize-url or fetch-status, but the specific output combination makes its core purpose distinguishable.

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 usage context is implied: use this tool when you need host, scheme, and HTTP status for a URL. However, it provides no explicit guidance on when not to use it or which sibling tool to prefer for overlapping needs.

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