sleeper_league_rosters

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

Beyond the annotations, the description discloses the full return shape, states that no auth is needed, and provides a join hint to map owner_id to human names. This adds useful behavioral context without contradicting the read-only and idempotent hints. It doesn't mention pagination or rate limits, but those are less critical for a simple single-league query.

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 well-structured with separate sections for purpose, return format, example, auth, and sibling relevance. It's concise and easy to scan, though the 'Also answers this' line is somewhat cryptic and could be clarified. Overall, every sentence contributes value.

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 one-parameter read-only tool without an output schema, the description provides a complete return structure, an example payload, auth status, and a cross-reference hint. It compensates well for the absent output schema. The only minor gap is the vague relationship with espnfantasy_rosters, but that doesn't hinder functional completeness.

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 already fully describes the only parameter (league_id) at 100% coverage. The description repeats its required nature and gives an example value, but does not add new semantic meaning beyond what the schema provides. Baseline of 3 is appropriate when the schema handles 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 clearly states it returns every roster in a league, including player IDs, starters, and season record, which identifies the resource and scope. It also distinguishes itself from the sibling espnfantasy_rosters by explicitly saying it answers that too. Although no explicit verb like 'get' is used, the phrasing is unambiguous.

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 usage for retrieving all rosters for a given league_id, and the example provides concrete context. However, it gives no explicit guidance on when to prefer this tool over other sleeper_* tools or when not to use it. The 'Also answers this: espnfantasy_rosters' line hints at cross-provider coverage but doesn't explain decision criteria.

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