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

Beyond the annotations indicating a safe read operation, the description explains that the tool returns a bounded payment sample and includes a disclaimer that reported relationships do not imply misconduct, providing valuable behavioral context.

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 concise with two sentences: the first states the main function and result, the second provides usage guidance. It is front-loaded and efficient.

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 the tool's simplicity, the description covers important context: bounded sample, disclaimer, and alternative tools. The output schema exists, so return values need not be detailed. Annotations and schema together provide sufficient completeness.

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 coverage is 75% with three of four parameters described. The description does not add parameter-level details beyond what the schema provides; it mentions 'exact NPI' and 'one program year' but does not elaborate on payment_type.

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 clearly states the tool finds CMS Open Payments records by exact NPI for one program year. It distinguishes itself from the sibling tool open_payments_search, which is used for name-based searches.

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 explicitly states when to use the tool (when exact NPI is available) and provides clear alternatives for name-based lookup: resolve via NPPES or use open_payments_search.

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