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

With no annotations provided, the description must fully disclose behavior. It only states the purpose but does not reveal side effects (e.g., whether it is read-only), authentication requirements, rate limits, or response format. 'URL reputation check' implies a query but leaves the agent guessing about operational traits.

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 short sentence, which is concise. However, the brevity sacrifices necessary detail, making it incomplete for an agent. It could be restructured as a clear action statement while maintaining conciseness.

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 tool's simplicity (1 parameter, no output schema, no annotations), the description is incomplete. It does not specify what the check returns (e.g., boolean, risk score), whether it is synchronous or cached, or any usage caveats. An agent would lack enough context to use it reliably.

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?

The input schema has one required parameter 'url', and the description does not add any semantic value beyond the schema's title 'Url'. With 0% schema description coverage, the description fails to compensate, e.g., by specifying URL format, constraints, or examples.

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 'URL reputation check (malware + phishing)' clearly indicates the tool's function: checking a URL's safety regarding malware and phishing. It uses a specific resource and domain, distinguishing it from sibling tools like 'calendar' or 'place'. However, it lacks an explicit action verb (e.g., 'check'), relying on a noun phrase.

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 does it mention any prerequisites or context. With 14 sibling tools, including some that might involve lookup or search, the lack of usage direction is a significant gap.

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