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

Annotations already declare readOnlyHint=true and openWorldHint=true, so safety is covered. The description adds genuinely new behavioral detail: the response includes every week id (enabling follow-up calls) and the NFL default is the current week, which is not derivable from the schema alone.

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 dense sentences, front-loaded with the returned fields and then the usage rules; nothing is wasted. The closing clause ("it needs league nfl, nba, mlb or college-football") is telegraphic and slightly redundant with the schema, keeping it just short of 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?

An output schema exists, so return values need not be explained, and the four parameters are fully described in both schema and description. The description covers the league-specific date/week constraints; only edge behaviors (out-of-season dates, pagination or result caps) are left unaddressed.

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%, so the schema already documents date, week, league, and end_date in equal or greater detail. The description restates the league enum and week/date defaults rather than adding new semantics, matching the baseline of 3 when the schema carries the load.

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?

States a specific verb and resource ("Get a FanDuel Sportsbook league's games") and enumerates exactly what each game record contains (teams, start time, status, venue, broadcast, scores). The league-scope wording implicitly separates it from team-scoped siblings like fanduel_sportsbook_team_schedule, but no sibling is named outright.

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?

Gives concrete routing guidance per league: NFL by week or by date range, college football by date range, NBA/MLB by date only. It explains the week-vs-date tradeoff and that week takes precedence by default, so an agent knows enough to pick parameters, though no alternative tool is explicitly named.

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