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

Annotations already declare readOnlyHint=false, openWorldHint=true and destructiveHint=false, so the mutation/open-world profile is known. The description adds significant behavior beyond that: asynchronous background execution with a ~10 minute duration, credit consumption, plan entitlement, a one-per-day cap, and automatic weekly re-checks. It stops short of describing progress/status reporting or what happens if a run fails, so a 4 rather than 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?

Front-loaded with the action and duration, then the sequencing instruction, then the cost/plan rules. Every sentence carries load-bearing information, but the pricing sentence is dense and comma/semicolon-chained, which makes it slightly harder to scan than an ideal definition.

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 parameters, no enums and no output schema, the description supplies everything the agent needs: trigger semantics, duration, follow-up tool, plan entitlement, credit cost, rate limit, and an explicit pre-call message requirement. Nothing an agent needs before invoking it appears to be 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?

The tool takes zero parameters, so there are no parameter semantics to explain and the schema cannot be contradicted or supplemented; baseline 4 applies. The description correctly conveys that everything (engine set, question count, runs) is fixed by the tool rather than configurable.

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 concrete action (run the AI visibility check) with exact scope: 10 buyer questions on every engine, 4 runs each, in the background for about 10 minutes. It clearly distinguishes itself from the sibling visibility tool by telling the agent to call visibility afterwards.

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?

Explicitly sequences the workflow ('call visibility afterwards'), states plan gating (first check free on every plan; re-checks need Builder or Growth), the cost (15 credits), the rate limit (at most one a day), and an interaction requirement ('State the price before a re-check'). When-to-use and when-not are both covered.

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