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

Annotations already declare readOnly/idempotent/non-destructive/closed-world, so the bar is lower, and the description still adds real context: plan gating (Lite or Pro), the auth mechanism (dashboard token as Bearer), the subscription-domain scope, and the exclusion of your own domain. It does not mention rate limits or pagination, but it goes meaningfully beyond the annotations.

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?

Four short sentences, front-loaded with what is returned and followed by auth and scope requirements. The one marketing-flavored sentence ("These are the pages to get mentioned on") still earns its place by conveying intended use; there is no filler.

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?

With no output schema, the description must carry the return-value burden, and it does partially by naming sites plus citation counts. However, it omits the time window covered by "answers," whether/how results are ordered or limited, and roughly how many sites come back. Auth and domain scope are covered, so it is adequate but not complete.

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?

There are zero input parameters, so the schema-versus-description comparison is moot and the baseline of 4 applies. The description correctly conveys that the only implicit inputs are the bearer token and the subscribed domain, neither being a schema parameter.

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 concrete resource and scope: the sites AI search engines cite most when answering buyer questions, with per-site citation counts and your own domain excluded. That is far more specific than the name alone. It stops short of explicitly separating this from siblings like who_wins_instead, so an agent must infer which one fits.

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?

"These are the pages to get mentioned on" hints at the downstream use (outreach/link acquisition) and the plan prerequisite plus Bearer-token requirement are spelled out. But there is no explicit when-to-use-this-instead-of guidance relative to who_wins_instead or get_visibility, so the routing decision is left implied.

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