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

Annotations already establish that this is read-only, idempotent, and non-destructive. The description adds useful context beyond that by specifying the scope ('the promotions the UFCalendar Fight API covers') and the exact capability flags returned (stats, rounds, rankings, broadcasts, predictions, scorecards), which helps agents understand the response without an output schema.

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 a single front-loaded sentence that names the action, the resource scope, and the key output detail. Every part earns its place, and there is no redundancy or unnecessary elaboration.

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 zero-parameter, read-only listing tool with rich annotations and no output schema, the description is complete: it states what is listed, the scope, and the fields an agent should expect. Nothing critical is missing for correct invocation or result interpretation.

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 input schema has zero parameters and schema description coverage is 100%, so there are no parameter semantics the description needs to document. The per-org capability flags mentioned are output content, not input parameters, so the description appropriately avoids parameter-related filler.

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 uses a specific verb and resource: it 'List[s] the promotions' the API covers, and further specifies the per-org capability flags included. This clearly distinguishes it from sibling list tools such as list_events and list_judges, as well as from get_* tools.

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 makes the usage context clear: use it to see which promotions/orgs the API covers and their capabilities. It does not explicitly name alternatives or exclusion conditions, but with zero parameters and a distinct resource type, the intended use is apparent and no conflicting alternative is suggested.

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