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

With no annotations provided, the description carries the full burden of behavioral disclosure. It details critical output semantics: the 'url' field is canonical, URLs must be used verbatim, and 'external_url' fields are not Spocal entities. This goes well beyond a basic list operation.

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?

The description is front-loaded with the purpose and every sentence earns its place by conveying essential usage rules around URL handling. It is concise without being under-specified.

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 simple list tool with no output schema, the description provides sufficient context: it explains the capped nature, the absence of schedule rows, and the key URL-related behaviors needed to correctly consume the results. It is complete for the tool's complexity.

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 schema already documents the single 'limit' parameter with its maximum and exclusivity. The description's 'capped set' aligns with the schema but adds no additional parameter-level detail, so the baseline score of 3 is appropriate.

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 clearly states the tool's function with a specific verb ('List') and resource ('supported competitions'), including the 'capped set' and 'without schedule rows' qualifiers. However, it does not explicitly differentiate from sibling tools like list_capabilities or preview_today_events.

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 provides clear context about what the tool returns and how to use the URLs, and the phrase 'without schedule rows' implies a limitation. However, it does not explicitly state when to use this tool versus alternatives or give when-not-to-use guidance.

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