List Sleeper leagues

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

The annotations already declare readOnlyHint=true and openWorldHint=true, so the description does not need to restate safety. It adds useful scoping context: 'configured user’s NFL leagues for a season' and the mapping purpose. However, it does not disclose additional behavioral details such as response shape, pagination, or how include_roster_ids affects the result. This is adequate but not rich behavioral disclosure.

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 sentences with no fluff. The first sentence states the action and scope, and the second provides immediate usage direction. Every word 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?

The tool is relatively simple and the description covers its core purpose and first-step usage. However, there is no output schema and the username parameter is not clearly explained in either the schema or description. The role of include_roster_ids is left to schema text. These gaps keep it from being fully complete, though annotations and context signals reduce the risk.

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 around 67%, with season and include_roster_ids documented in the schema but username left undocumented. The description adds some meaning via 'configured user’s', which hints at username's role, and 'for a season' aligns with the season parameter. It does not add detail about include_roster_ids, but the schema already describes that parameter. Overall, the description partially compensates for schema gaps without fully clarifying all parameters.

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 states a specific verb and resource: 'List the configured user’s NFL leagues for a season.' It also clarifies the intended output purpose with 'map league names to league IDs,' which distinguishes it from sibling tools like sleeper_league_overview. This is more than adequate for an agent to understand what the tool does.

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 gives clear usage context: 'Use this first to map league names to league IDs.' This tells an agent when to invoke it, but it does not explicitly mention when not to use it or name alternative tools. It stops short of the rubric's strongest level.

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