Roster-User Mapping

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

Annotations already indicate readOnlyHint=true and openWorldHint=true, but the description adds no additional behavioral context (e.g., rate limits, pagination, or confirmation of read-only nature). Since the description does not contradict annotations and provides minimal extra transparency, it scores a 3.

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, concise sentence of 8 words that communicates the tool's purpose without unnecessary detail. It is front-loaded and efficient, earning a 5.

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?

With a simple parameter set, annotations covering read-only behavior, and an output schema (though not analyzed), the description provides the core purpose. However, it lacks details on prerequisites or error conditions, so it is slightly incomplete for a tool with zero schema description coverage, scoring a 4.

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 has 0% description coverage, and the tool description only adds the context 'for a league', which minimally clarifies that the league_id parameter identifies the league. This adds little meaning beyond the schema's type and title, resulting in a score of 2.

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 clearly identifies the resource as a 'mapping of roster IDs to user names' scoped to 'for a league'. This distinguishes it from siblings like 'get_league_rosters' and 'get_league_users' which provide separate lists.

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 no guidance on when to use this tool versus the sibling tools (e.g., get_league_rosters, get_league_users). It only states the tool's function without any context for selection, scoring a 2.

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