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

With no annotations, the description carries the full burden of behavioral disclosure. It only states that the tool performs a HEAD request and returns status, without mentioning side effects, error behavior, rate limits, or what happens to the other parameters (though the schema notes they are 'discarded'). This minimal disclosure is insufficient for a tool with nine optional inputs.

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 sentence with no filler, making it concise and front-loaded. However, given the tool's complexity (9 parameters, no output schema), the brevity borders on under-specification, though it still earns a high score for efficiency.

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 is incomplete for a tool with 9 optional parameters, no output schema, and no annotations. It doesn't explain what the 'status' output looks like, how the other parameters influence behavior, or any use context. The mismatch between the description and the schema leaves significant gaps.

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 each parameter has a clear description (e.g., 'discarded after the shape check'). The tool description adds no parameter meaning beyond the schema; it only implicitly refers to 'url'. Since the schema already documents each parameter, the baseline of 3 applies, and the description provides no additional semantic value.

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 operation ('HEAD a public URL and return status only'), but the schema lists 9 parameters, many of which (city, zone, query, json, path, etc.) are unrelated to URL HEAD requests. This mismatch muddies the purpose; it's clear for the URL case but doesn't explain the other parameters, so the description is only partially clarifying the tool's scope.

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 like browser-url-ok, playwright-url-ok, or normalize-url. It doesn't mention any exclusions or conditions, leaving the agent to infer appropriate usage.

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