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

Annotations already declare readOnlyHint, idempotentHint, openWorldHint, and destructiveHint=false, so the safety profile is covered. The description adds the credit cost and the fact that appointment/resignation dates come back, but says nothing about pagination, volume of officers returned, or how activeOnly changes results.

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?

A single front-loaded sentence plus a parenthetical cost note; nothing is wasted and the resource is stated before the cost.

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 read tool with fully documented parameters and no output schema, the description does cover what comes back qualitatively (officers plus appointment/resignation dates) and the credit cost. Only minor gaps remain, such as result volume or whether resigned officers appear by default.

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%, so both parameters are documented in structured form and the baseline is 3. The description's mention of appointment and resignation dates subtly hints that historical officers may be included (relevant to activeOnly), but it adds no explicit parameter semantics.

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 (directors and secretaries) keyed to a company number, which is clear enough to distinguish it from siblings like company_pscs or company_filings. It does not explicitly name those alternatives, so it falls short of a 5.

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?

Implicit guidance only: the phrase 'for a company number' signals that a company number is the prerequisite, but there is no explicit when-to-use, when-not-to-use, or pointer to company_pscs/company_profile for related queries.

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