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

Annotations already declare readOnlyHint=true and openWorldHint=true, so the safe-read profile is covered. The description usefully adds that the call takes no arguments and that the output contains league identifiers for downstream event tools, but no further behavioral detail beyond that.

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?

Two tightly written sentences with no filler; the catalog purpose and the downstream use are both front-loaded and each sentence earns its place.

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?

An output schema exists, so return values need not be described, and the description supplies the one thing an agent needs — that it yields identifiers for event tools. It could say more about coverage (all sports vs featured) to fully disambiguate from siblings.

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?

The tool has zero parameters, which is the baseline-4 case. The description reinforces this by noting it is a 'no-argument catalog,' consistent with the empty schema.

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 DraftKings Sportsbook's current sports and league directory,' and adds that it returns league identifiers used by event tools. It does not explicitly distinguish itself from the sibling draftkings_featured_leagues, so an agent must infer the difference between the full directory and the featured subset.

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?

Explicitly tells the agent to use this 'no-argument catalog to discover a league before browsing its schedule or markets,' which names the downstream tool sequence (schedule/markets). It lacks any when-not guidance or direct naming of the sibling alternatives.

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