Get Leagues for User

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

No annotations are provided, so the description must carry the full behavioral burden. It only restates the core function and does not disclose return shape, list vs. empty behavior, error handling, ordering, or any side effects or limitations. An agent gets little more than the tool name conveys.

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 no filler. Every word contributes to the core purpose, making it easy to parse quickly.

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?

Given there is no output schema and no annotations, the description should fill in what the returned data looks like. It does not, nor does it clarify default season behavior beyond the schema, failure modes, or whether the result is an array. For a tool with only two well-described parameters, invocation is straightforward, but response expectations are ambiguous.

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 description coverage is 100%, with both 'user_id' and 'season' described. The description adds no new parameter meaning beyond restating 'a user belongs to' and 'given season', which is already present. Baseline 3 applies because the schema handles the parameter documentation.

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 ('Get') and resource ('all leagues'), with a clear scoping clause: 'a user belongs to for a given season.' It clearly differentiates from sibling 'get_league' by being plural, and from 'get_users_in_league' by inverting the relationship.

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 implies when to use it: when you need all leagues for a specific user and season. However, it provides no explicit guidance on when not to use it, no alternatives, and no prerequisites such as the user_id needing to exist or season format.

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