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

Annotations already declare this read-only, idempotent and non-destructive, so the safety profile is covered. The description goes well beyond that by disclosing metered/billing behavior tied to the account, access and delay variability, a no-retry/no-polling constraint, the exclusion of affiliate 27, and the important caveat that an empty result does not mean no coverage.

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?

It is compact overall, but the opening is a run-on with no punctuation ('List all sports Read-only Product data or price calculation'), jamming the purpose and a policy phrase together. Later clauses are dense and mix billing, retry policy, affiliate exclusion and result-interpretation without clear ordering.

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 an output schema present and zero parameters, the description need not explain return values and doesn't. It covers the operational caveats an agent needs (metered usage, no retry, empty results not implying absence), though it omits any note on result size or how the canonical sport IDs relate to the sibling sport-scoped tools.

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?

This is a zero-parameter tool, so the baseline is 4 and there is nothing for the description to clarify about arguments. It correctly adds no spurious parameter detail.

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 verb and resource ('List all sports'), so the operation itself is unambiguous. However, it offers no differentiation from the closely related siblings 'list_sports' and 'v2GetSports', leaving the agent to guess which version to call.

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 never says when to use this tool versus 'list_sports' or 'v2GetSports'. 'Use returned canonical IDs' is downstream advice for chaining calls, not selection guidance, and 'never infer coverage from an empty result' is a caveat rather than a when-to-use rule.

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