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

Annotations already declare readOnlyHint=true and openWorldHint=false, so the safe-read profile is covered. The description adds no further behavioral detail such as pagination, result limits, or ordering. With annotations carrying the safety burden, this is adequate but thin.

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 with zero filler; the resource and its optional filters are packed into one efficient clause.

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?

For a filter-list tool with no output schema and annotation-covered safety, the description supplies what an agent needs: the entity returned and the available filters. Minor gaps remain around result ordering and pagination, but nothing essential to calling it correctly is missing.

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 0%, so the description must carry the parameter load, and it does: it names all three filters and enumerates the valid division values (open, pro, doubles, pro_doubles, relay, adaptive), which is meaningfully more than the bare schema. It does not specify the country format (e.g. ISO code) or race slug shape, keeping it from a 5.

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 HYROX athletes looking for sponsors'), which is clearly distinct from sibling search_races and the get_athlete lookup. It does not explicitly name an alternative tool, so it falls short of a 5.

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 word 'optionally' implies all filters are optional and the tool works as a broad discovery list, but there is no explicit when-to-use or when-to-prefer-get_athlete guidance. Usage is implied by the sponsor-seeking framing rather than stated.

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