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

Annotations already declare readOnlyHint and openWorldHint, so safety is covered. The description adds real value by disclosing the returned data shape (bet/money splits, last five results) and the implicit caveat that only events with published stats are included, but it says nothing about result volume, pagination, or freshness.

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 compact clauses with the resource and payload up front and the optional filter last. No filler, no restatement of the tool name.

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 and annotations cover safety, so the description only needs to frame scope and payload, which it does. The one remaining gap is routing guidance relative to the many other FanDuel stats/odds siblings.

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 coverage is 100% and the schema already documents competition_id with a concrete example (12282733 for the NFL). The description only adds that the filter is optional, which is a marginal gain over the structured field.

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 (list upcoming FanDuel Sportsbook events) and enumerates the payload precisely (bet share, money share per side of spread, last five results). It does not explicitly contrast with near siblings such as fanduel_sportsbook_event_stats, team_odds, or market_prices, so an agent must infer the distinction from the field list.

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?

Usage is only implied: the tool lists all upcoming events and optionally narrows by competition_id. There is no statement of when to prefer this over fanduel_sportsbook_team_odds or fanduel_sportsbook_event_stats, and no exclusions (e.g., that only events with published stats appear).

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