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

Annotations establish this is a write (readOnlyHint=false) but non-destructive and idempotent; the description adds genuine context beyond them: it previews by default and only commits when confirm is true, and that it grants the signed-in Google account ownership in Search Console. It does not mention auth/permission requirements or failure modes, keeping it below a 5.

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?

Three tight sentences that front-load the core action, then state the effect and the preview default. No filler or redundancy.

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 two-parameter mutation with no output schema, the description covers the prerequisite, the side effect, and the preview/commit mechanism. Nothing essential to invoking 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 coverage is 50%: confirm is fully documented in the schema, while site_url has no description. The description echoes the confirm semantics ('previews unless confirm is true') without adding syntax, and only implies site_url via 'a client's site.' Baseline 3 is appropriate given the partial coverage.

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?

States a specific verb (verify ownership) and resource (a client's site in Search Console), and explicitly names the sibling tool site_verification_token as the source of the required token. An agent can distinguish this from site_check and site_verification_token without opening any schema.

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?

Gives a clear precondition: run it 'once the token from site_verification_token is live on it,' which tells the agent the ordering relative to the sibling. It does not name explicit exclusions or when-not-to-use conditions, so it falls short of a 5.

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