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

Annotations already cover the read-only, idempotent, non-destructive profile. The description adds useful behavioral context beyond annotations: the backtest performance of team units versus skater Elo and the important caveat that skater Elo is a ranking rather than a projection. It does not discuss rate limits, auth, or pagination 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 core definition is front-loaded and the view breakdown is orderly. The single dense paragraph is efficient overall, though it could be slightly more scannable and the final sentence about backtests, while useful, adds minor length.

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 the important work of explaining what each view returns. It covers purpose, view modes, and model caveats, but leaves some parameter interactions (team filtering, limit behavior) to the schema and does not describe response format details.

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%, and the description thoroughly explains the view enum values (tonight, teams, players, accuracy), which compensates for the missing schema description on that parameter. It does not explain how the team, limit, or position parameters interact with each view, though the schema provides descriptions for those.

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?

States a specific resource (NHL Elo ratings), explains the scale (1500 average, higher is better), and specifies the four views available. It distinguishes this tool from projection tools by noting that skater Elo is a ranking, not a projection, and that NHL projections do not use Elo.

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?

Clearly explains the default view and what each view returns, giving strong context for selecting between modes. It also implicitly steers agents away from using this for projections, but it does not explicitly name alternative sibling tools or state when not to use this tool beyond that one caveat.

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