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

Annotations already declare readOnly, idempotent, non-destructive, closed-world behavior, so the safety profile is covered. The description adds genuinely new context: the payload is deliberately truncated preview data (whistle rate reduced to "a word," accuracy shown only "when it stands out"), which tells the agent to expect partial/null fields and not to treat this as a complete profile.

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?

Two short sentences, front-loaded with the resource and scope, then the caveat about preview data. Every clause maps to either the returned fields or the truncation warning; nothing is 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?

With no output schema, the description does its job by enumerating the three returned signals and flagging that they are abbreviated. What's missing is edge-case behavior — e.g., what happens for an unknown or ambiguous referee name — which matters for a lookup keyed on a free-text string.

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 100% and the single name parameter is documented with an example ('Scott Foster') plus length bounds. The description contributes nothing further about the parameter, so the schema carries the load and a baseline 3 is appropriate.

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?

"A short read on one NBA referee" pairs a specific verb-and-resource with the field set it returns (whistle tendency, late-game accuracy, next assignment), so the agent knows it takes a single referee name rather than a game or a nightly slate. It doesn't explicitly name nba_game_refs or nba_refs_tonight, so the sibling distinction is inferred from "one" rather than stated.

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?

There is no explicit when-to-use or when-not-to-use statement and no sibling is named as an alternative. The closest thing to guidance is "Preview only: the full profile is on WhistleBets," which implies this is a shallow lookup and not the source for complete referee profiles, leaving the agent to infer selection rules.

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