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

With no annotations, the description carries the full burden and does well: it discloses that the capability is not yet served, that calling it records the requirement, and that the return is a structured not-covered response. It does not detail what recording the requirement entails, but the key behavioral surprise is clearly surfaced.

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 description is a compact pair of clauses, with the critical status (not yet served) front-loaded. Every phrase contributes to explaining the tool's stub nature and its side effect.

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 one-parameter stub with no output schema, the description gives the essential context: no real resolution data is returned and a structured not-covered response is produced. It could specify the response fields more concretely, but nothing critical for correct invocation is 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 schema has 100% description coverage for the single company_number parameter, so the parameter is already documented structurally. The description does not add format or meaning beyond what the schema provides, which is the expected baseline when schema coverage is complete.

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 specific resource (UK beneficial-ownership chain from PSC data) and explicitly labels the tool as a roadmap probe that is not yet served. It does not explicitly name sibling alternatives such as request_data or find_capability, but the non-functional status is clear enough for an agent to understand what this tool does.

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?

The description implies usage by saying that calling it records a requirement and returns a not-covered response, which tells the agent when the tool is applicable. However, it does not say when to avoid it or point to an alternative for recording capability requests, leaving routing against request_data and find_capability implicit.

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