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

The description mentions that page content is not stored, giving some insight into the tool's side effects. However, it does not disclose potential network requests, error handling, rate limits, or whether the operation is read-only. Without annotations, this level of transparency is incomplete.

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 extremely concise, using two short sentences to convey the core function and a key limitation. There is no redundant or irrelevant content, and the structure is easy to parse.

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 description fails to explain how the nine optional parameters should be used, which one is the primary input, or how they relate to the output. It omits examples or clarifications that would help an agent decide what to pass. The tool appears to be a simple citation checker, but the parameter ambiguity prevents full self-contained understanding.

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?

Although every parameter has a description, most descriptions are generic mismatches (e.g., 'city' as a weather hint, 'ref' as a Git ref) that do not relate to the tool's stated purpose of returning host/scheme/status for a URL. The 'url' parameter description is relevant, but the roles of the other eight parameters remain confusing and unexplained.

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 precisely what the tool does: it returns the host, scheme, and HTTP status for a URL. It also explicitly notes that page content is not stored, which clarifies the tool's scope. This is specific and actionable for an agent.

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 provides a hint about when to use the tool (when only host/scheme/status are needed, not content) but does not explicitly mention alternative tools or conditions for selection. It lacks guidance on how to choose this over similar siblings like fetch-status or web-fetch.

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