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

Annotations already declare readOnly, idempotent, non-destructive and closed-world, so the safety profile is covered. The description adds value beyond that by disclosing the return shape (ranked list plus the URL of its table) and a tier gate (Pro adds offense/defense, box prior, RAPM and on/off components). It doesn't mention result size limits or how partial seasons are handled, which keeps it from a 5.

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?

Three sentences, front-loaded with the usage trigger, followed by the covered list and the exclusion. No redundant restatement of the title or annotations, and every clause carries information.

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 takes on the burden of describing returns and does so (ranked list with table URL, Pro-only components). For a read-only, closed-world leaderboard tool with fully documented parameters, that is nearly everything an agent needs; only pagination/result-size behavior is unstated.

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% with two enums, so the schema already documents all three parameters thoroughly; baseline 3 applies. The description loosely maps natural-language requests to kinds, but the example "top 10 NFL defenses by EPA" sits ambiguously between power_rankings and efficiency, so it adds marginal rather than clarifying value.

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 opens with a specific trigger ("user asks for a league-wide list") and enumerates the exact resources covered: standings, NBA Keel Impact ratings, NFL EPA per play, weekly power rankings. It explicitly carves out what it is not ("Not for one team or player"), so an agent can distinguish it from team_profile and player_profile without opening any schema.

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?

It states both the when (league-wide ranked lists) and the when-not (single team or player), and names the correct alternative ("use their profile"). The example phrasing "top 10 NFL defenses by EPA" gives the agent a concrete pattern to match user requests against.

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