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

Annotations already cover the safety profile (readOnly, idempotent, non-destructive, closed-world), so the description is freed to add semantics — and it does: it attributes the figures to the free Dixon-Coles model from Docteur Bet and explains the scale (1 = league average; a lower defence figure is better). It does not cover failure behavior for an unknown competition, keeping it short of 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?

A single front-loaded sentence that states the purpose first and then enumerates the returned figures; every clause earns its place. The nested parentheticals make it dense, but there is no filler or repetition.

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 correctly carries the return-value burden, listing attack strength, defence strength, overall index, and the rank-vs-position gap, plus interpretation rules. It falls short only on edge behavior (what happens when the competition is unknown or has insufficient data).

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%, so both parameters (competition, lang) are already fully documented in the schema, and the description adds nothing about their format or behavior. Baseline 3 applies when the schema carries the parameter burden.

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 names a precise resource and verb: it returns the power ranking of a competition, with attack/defence strength, an overall index, and rank-vs-table gap. This is plainly distinct from the match- and projection-oriented siblings (get_match_probabilities, get_season_projection), so an agent can route to it without opening the 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?

There is no explicit when-to-use or when-not guidance and no sibling is named as an alternative for related questions (e.g., season projections or match probabilities). The closest thing to guidance is the implicit framing of output content, which is descriptive rather than directive.

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