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

Annotations already declare readOnlyHint and idempotentHint, so the safety profile is known. The description adds a valuable behavioral note that affiliation data is self-reported and that absence does not imply no affiliation, which is critical for correct interpretation. It also mentions the specific fields returned (organization names, identifiers, etc.), enriching the behavioral context beyond annotations.

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 three sentences, each carrying weight: purpose, parameter control, and data caveat. It is front-loaded with the primary action and remains free of redundant phrasing. Every sentence earns its place without padding.

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?

The tool is a straightforward read operation with an output schema available. The description covers the purpose, parameter behavior, returned fields, and a crucial data-quality caveat. There is no missing information an agent needs to invoke it correctly or interpret results appropriately.

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?

Input schema covers 100% of parameters with descriptions, so the baseline is 3. The description reinforces the types parameter's meaning by listing all acceptable values and the default, and adds context on what the returned data contains. It slightly exceeds the schema by explaining the output fields, but does not add significant new param-level semantics beyond what the schema already provides.

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 uses a specific verb ('Fetch') and resource ('affiliation records for an ORCID researcher'), and clearly differentiates from sibling tools by focusing on affiliations. It states the exact scope and lists the types parameter's possible values, leaving no ambiguity about what this tool retrieves.

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 provides clear context on when to use this tool (to fetch affiliations) and explains the default behavior of the types parameter. However, it does not explicitly reference sibling tools or state when to choose an alternative (e.g., if needing funding or peer reviews), so the guidance is implied rather than explicit.

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