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

Annotations already declare readOnlyHint, idempotentHint, and destructiveHint=false, covering the safety profile. The description adds context about the data category and its significance but does not disclose operational behavior such as response shape, pagination, or auto-discovery of the latest year (the latter is covered in the schema instead).

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 single, tightly worded sentence that front-loads the tool's scope and adds a useful qualitative signal ('strongest conflict-of-interest signal'). There is no redundant phrasing or filler.

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?

Given six optional parameters fully documented in the schema, read-only annotations, and a clear domain statement, an agent has enough to select and invoke the tool correctly. The main gaps are the lack of return-value/output-shape guidance and no explicit routing among the many open_payments_* siblings, but these are partially mitigated by the ownership-specific naming and description.

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 all six parameters are already documented with meaningful descriptions. The tool description adds no parameter-level detail beyond the schema; it only reframes the domain as ownership/investment-interest, which the schema's 'doctor' and 'company' fields already convey.

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 action ('Search') and a specific resource ('Open Payments OWNERSHIP / investment-interest data'), and it clarifies the target population: doctors with equity stakes in pharma/device companies. This distinguishes it from the many other open_payments_* siblings by focusing on ownership/investment interest rather than general payments or aggregated statistics.

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 clearly conveys when to use this tool: when the agent needs ownership/investment-interest data or the strongest conflict-of-interest signal from Open Payments. It does not explicitly name sibling alternatives or exclusion conditions, so it stops short of a 5, but the use case is explicit rather than merely implied.

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