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

Annotations already declare readOnlyHint, idempotentHint and non-destructive behavior, so the safety profile is covered. The description adds genuinely new context above that bar: a guest call returns 401 and triggers the OAuth flow, plus the result ordering (newest first).

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?

Two compact sentences, front-loaded with what the tool returns before the auth caveat. The field enumeration is slightly redundant given an output schema exists, but it is short and readable.

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 single-optional-parameter, read-only list tool with an output schema, the description covers scope, ordering and the auth failure mode. Return-value details are legitimately left to the output schema, so nothing an agent needs to call it correctly is missing.

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% and the single limit parameter already documents its range and default of 20. The description's 'newest first' matches the schema and adds no syntax or format detail beyond it, so the baseline of 3 applies.

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 names a specific resource (the signed-in account's AI visibility audits) and enumerates the returned fields, so the agent knows exactly what comes back. It scopes itself to the signed-in account, which separates it from site-analysis tools, but it never names the nearest sibling (visibility_history) to draw a hard line.

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?

Auth context is given (signed-in account required), which implies when the call will succeed, but there is no explicit when-to-use/when-not guidance and no alternative tool is named. Usage is inferable rather than stated.

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