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

Because no annotations are provided, the description carries the full burden of behavioral disclosure. It does add useful context: the formula, same-hour per-game aggregation, the min 500 player threshold, and the >1.0 interpretation. But it omits output shape, ordering, pagination, and how the optional genre parameter changes behavior.

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 with no filler: first defines the metric, second explains what values mean, third gives a signal use case. It is front-loaded and efficient, though some interpretive prose could have been replaced with operational detail.

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 and no annotations, the description needs to explain what the tool returns and how the genre parameter works. It explains the aggro concept well but leaves out essential invocation and response details, making it incomplete for an agent deciding how to call it.

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 0% and the description never mentions the only parameter, 'genre'. The agent cannot infer whether genre filters results, groups them, or changes the metric calculation. This is a significant gap because the description must compensate for the undocumented schema but does not.

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 defines the aggro metric (live Twitch viewers / concurrent Steam players) and its interpretation, but it never states the tool's actual operation—no verb like 'list', 'compute', or 'return'. It tells the agent what aggro means, not explicitly what aggro_board does or returns.

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 a use case ('A sudden aggro jump is an early attention signal') and notes watch-to-learn genres, which hints at when the tool might be relevant. However, it does not compare against siblings like hype_board, top_watched, or top_played, nor does it state when not to use this tool.

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