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

With no annotations, the description must carry full behavioral disclosure. It only adds 'Page content is not stored,' which is a helpful retention/privacy trait, but it omits significant behavioral details such as network side effects (making an HTTP request), rate limits, or what data (if any) is retained beyond page content.

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 the primary action front-loaded. 'Page content is not stored' earns its place as a behavioral note. No wasted words.

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?

Given no annotations, no output schema, and four parameters across multiple domains (URL, host, JSON, timezone), the description is too sparse. It does not explain how the parameters fit together, what the tool returns beyond host/scheme/status, or when the additional parameters are required. This leaves an agent under-informed for a tool with broad 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% and each parameter has a description, so the schema already documents the parameters. The tool description does not add meaningful semantics beyond the schema, such as how url, host, json, and zone relate to each other.

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 action: 'Return host, scheme, and HTTP status for a URL.' This is a concrete verb+resource pair. However, it does not mention the json or zone parameters, which weakens its completeness for a tool that appears to also validate JSON and timezones.

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, nor any exclusions or prerequisites. There is no mention of when the json or zone parameters would be relevant, leaving the agent to infer usage from parameter names.

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