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

Annotations already declare readOnlyHint=true, destructiveHint=false and openWorldHint=false, so safety is covered; the description adds genuinely useful return-shape information ('each with its name', 'empty list when none are recorded') that no annotation or output schema provides. It omits any note on permissions or scoping of the corporate secretary profile, keeping it out of the top tier.

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 sentences, zero filler: what it returns, the empty-case behavior, and the sibling routing are each front-loaded and distinct. Nothing redundant with the name or title.

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 annotations covering safety and no output schema, the description supplies everything needed to invoke it correctly: scope, return shape including the empty case, and where to go for adjacent company data.

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 is a single parameter ('id' as Company ID) and schema description coverage is 100%, so the schema already carries the semantics. The description adds no format, source, or lookup detail (e.g. where to obtain the ID) beyond the schema, which is the expected baseline at full 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 and resource ('List the subsidiaries recorded in a company's corporate secretary profile') and immediately names the adjacent siblings (get-directors-shareholders, get-company), so the agent can tell it apart without opening another schema. No ambiguity about scope.

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 routes the agent to the two closest alternatives for related data (directors/shareholders, company itself), which is strong sibling differentiation. It stops short of stating a when-not condition or prerequisites for using this tool, so it falls just under the top tier.

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