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

With no annotations, the description bears full responsibility for behavioral disclosure. It reveals that the body is discarded and implies public URLs need no auth, but it does not mention rate limits, error behavior, or side effects, and it contradicts the schema by ignoring the extra parameters.

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 only two short sentences, but it is under-specified for a tool with 9 parameters and a complex web of siblings. It is not concise in a helpful way; it omits essential context.

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?

There is no output schema and no explanation of return values, no mention of which parameters are actually used, and no guidance on how the tool relates to siblings. An agent cannot confidently call this tool with the right parameters or interpret results.

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 descriptions cover all 9 parameters, so that baseline is met, but the tool description adds no clarification about why parameters like 'city', 'zone', or 'query' exist when the stated purpose is fetching URLs. The description fails to reconcile the mismatch between its core function and the full parameter set.

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 clear action and resource ('HTTP status and content type for a public URL'), but it does not differentiate from siblings like fetch-status or browser-url-ok, and it omits any mention of the tool's many unrelated parameters (city, zone, query), making its actual scope ambiguous.

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 given on when to use this tool versus its siblings, nor any exclusion criteria. An agent has no way to know if this is the right tool for a given task among 28 similar tools.

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