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

With no annotations, the description must disclose behavioral traits. It only states 'Page content is not stored,' which is a privacy note, but does not mention side effects, network behavior, error handling, or that many input parameters are discarded after checks. This is minimal disclosure for a tool with such a broad schema.

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, efficient sentence with the primary output front-loaded and an additional privacy note. There is no wasted wording, and it is appropriately brief for the stated function.

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 having 9 optional parameters and no output schema, the description only explains the URL-related behavior. It does not clarify what happens with the other parameters (city, feed, json, etc.), which the schema indicates are discarded after checks, nor does it describe the return format beyond host/scheme/status. This is a significant gap for an agent trying to understand the tool's full scope.

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 100%, meaning all 9 parameters are already documented in the schema. The description itself adds no parameter semantics beyond the schema, so the baseline score of 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 the core function: 'Return host, scheme, and HTTP status for a URL.' This is a specific verb+resource with a defined output. However, it does not explicitly differentiate from sibling tools like fetch-status or normalize-url, which may also return URL-related information.

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 no guidance on when to use this tool versus alternatives. It does not mention any prerequisites, exclusions, or scenarios where another tool would be preferred. The agent is left without direction on selecting this over similar URL tools.

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