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

Annotations already establish read-only and non-destructive behavior. The description adds meaningful extra context: the call is paid, and partial failures return isolated results. It does not cover rate limits or output details, but the incremental behavioral disclosure is valuable.

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 dense sentence that covers scope, cost, batching, and failure isolation without filler. It is front-loaded with the verb and object, making it easy to scan.

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 simple two-parameter read-only tool with annotations, the description is mostly functional: it explains the core urls parameter, the batch limit, and the paid nature. However, it leaves expectedStatus meaning, the precise meaning of 'check', and the response shape unspecified, and there is no output schema to fill that gap.

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 0%, so the description must compensate for parameter meaning. It adds useful context for urls ('public', 'up to ten'), but it completely omits expectedStatus, including its optionality and meaning. An agent would have to infer expectedStatus from the property name and schema constraints.

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 the action ('Check'), the resource ('up to ten public URLs'), and the batching mode ('in one paid call'). It does not explicitly differentiate from siblings like verify_web_evidence, and 'check' leaves the exact nature of the check somewhat implicit.

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 implies the tool is for checking multiple public URLs in a single paid call, which gives useful context. However, it provides no explicit guidance on when not to use it or which sibling tool to choose instead, so the agent must infer the appropriate usage.

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