get_league_rosters

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

Annotations already declare readOnlyHint, openWorldHint, idempotentHint, and destructiveHint, covering safety. The description adds behavioral context by enumerating exactly what data is returned (roster_id, owner_id, players, starters, wins, losses, points, etc.) and scoping it to 'every roster' in the league. It does not conflict with annotations.

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?

Three sentences, no fluff. The first sentence states the action, the second lists included fields, and the third gives workflow guidance. Info is front-loaded and every sentence contributes to clarity.

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 read-only tool with one fully-documented parameter and no output schema, the description covers purpose, available fields, and how to obtain the required input. It also hints at the response structure ('every roster'). Nothing essential is missing for an agent to call it correctly.

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%; the parameter 'league_id' is already described as 'Sleeper league_id obtained from get_user_leagues.' The description repeats this exact guidance without adding any new semantic details (e.g., format, validation rules, or variations). Baseline 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 'Return every roster and its season record in a Sleeper league' with a specific verb and resource. It lists the roster fields and distinguishes itself from siblings like get_league_users (which maps owners) and get_league_matchups (scoreboard). No ambiguity.

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?

Provides explicit workflow guidance: 'Obtain league_id from get_user_leagues. Combine with get_league_users to map owners to teams and use for standings or roster analysis.' This tells when to use the tool, how to get its input, and how to combine it with a sibling, effectively routing the agent to the correct usage.

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