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

With no annotations provided, the description carries the full burden. It only states that page content is not stored, which is one side-effect trait. It does not disclose whether network requests are made, whether the operation is read-only, or any other potential side effects. This is insufficient for a tool with no annotations.

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 brief, directly to the point, and contains no unnecessary words. Two sentences efficiently convey the core function and a key side-effect limitation.

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 the presence of four parameters that suggest multiple modes (URL, host, JSON, timezone), the description does not provide enough context to understand when or how to use each parameter. The tool is not fully self-explanatory, leaving the agent to guess the intended usage pattern.

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?

Each parameter has a description, but they do not align with the tool's stated purpose. The description only mentions URL, yet there are parameters for host, json, and zone that imply different functions. The relationship between these parameters and the tool's behavior is not explained, leaving significant ambiguity.

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 that this tool returns host, scheme, and HTTP status for a URL, which is a specific and actionable verb-resource pair. However, the presence of unrelated parameters (json, zone) and sibling tools like normalize-url creates minor ambiguity about the exact scope, so it is not a perfect 5.

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 gives a clear context: when you need host, scheme, and HTTP status for a URL, use this tool. It also implies a side-effect limitation with 'Page content is not stored.' However, it does not explicitly mention when not to use alternative tools or provide exclusions, so it falls short of a 5.

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