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

The description discloses one behavioral trait: page content is not stored. But with no annotations, it carries the full burden and does not mention whether network calls are made, whether it is read-only, or what side effects occur. The schema hints at some behaviors (e.g., 'no disk access' for path), but the description does not consolidate these.

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 sentences with no filler. The primary purpose is front-loaded, and the privacy note adds value without waste. This is an example of efficient writing.

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 tool with 9 unrelated parameters, no annotations, and no output schema, the description is grossly incomplete. It only addresses URL citation, while the schema accepts city, feed, json, path, timezone, etc., leaving an agent unable to understand the full scope or appropriate usage.

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%, so the schema fully documents each of the 9 parameters. The description adds no parameter-specific meaning beyond what the schema already provides. Baseline 3 is appropriate given full schema coverage.

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 specific verb and resource: returning host, scheme, and HTTP status for a URL. However, it fails to distinguish from siblings like fetch-status or normalize-url, and the 9-parameter schema suggests a far broader scope than URL citation, creating ambiguity about what the tool actually does.

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?

No guidance is provided about when to use this tool versus alternatives. There is no mention of use cases, exclusions, or why this tool exists alongside siblings. The description gives no context for selecting it.

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