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

Annotations already declare readOnlyHint=true, destructiveHint=false, and openWorldHint=false, so the safety profile is covered. With no output schema, the description usefully discloses the return payload (status, rank, evidence grade, gaps with fixes, correction reporting) and adds the policy note that ranks are not purchasable. It stops short of auth or rate-limit details, but adds real value 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?

The opening question front-loads purpose and the return-value sentence follows immediately. It is slightly list-heavy, and the closing 'Ranks are never for sale' line is more positioning than instruction, but it is short and nothing is buried.

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-parameter read tool with no output schema, the description supplies what the schema cannot: a full inventory of returned fields and the remediation angle. The main omission is any sense of result size or what happens when a company is not found, which the annotation set does not cover.

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 parameter already documents 'Company name or website' with an example. The description's 'Give a company name or website' restates that without adding format or matching semantics, so the baseline 3 for schema-heavy tools 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 states a concrete verb (check) and resource (a company's SalesBook listing) and enumerates the dimensions returned: listing status, sector and rank, evidence grade, agent-readiness, and ranking gaps. It reads as a multi-dimensional audit, which implicitly separates it from narrower siblings like get_ranking or get_profile, but it never names or contrasts those siblings explicitly.

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?

It gives an audience ('For founders and vendors') and an input rule ('Give a company name or website'), which implies when the tool applies. However, there is no explicit when-not guidance and no routing to alternatives such as get_ranking for leaderboards or get_profile for other detail, leaving the agent to infer boundaries.

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