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

Annotations already declare this is a safe, idempotent, closed-world read, so the description only needs to add content-level context — which it does by enumerating what is returned (scores, pre-game probabilities, starters, injury changes). What it does not disclose is how 'tonight' is resolved without a date (timezone/rollover) or how stale/live data is refreshed.

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?

A single front-loaded sentence that packs the resource, the date variation, and the full payload list with no filler. Nothing is redundant with the title.

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 no output schema, the description usefully inventories the return payload, which is exactly what an agent needs to decide whether to call it. Minor gaps remain: how the default 'current/next slate' boundary is determined and whether probabilities are model-derived or book-sourced.

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%, so both parameters (date format, league enum) are fully documented in the schema. The description reinforces the date parameter's optional nature and league options but adds no format or edge-case detail beyond the schema, so the baseline 3 applies.

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?

Uses a specific verb ('Get') with a precisely enumerated resource set: tonight's or a given date's NBA/NFL games, live/final scores, pre-game win probabilities, NBA last-game starters, and injury status changes. None of the sibling tools (game_projection, injury_consequences, player_profile) covers a daily slate, so the scope 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 parenthetical '(or a specific date's)' implicitly tells the agent when to supply a date, but there is no explicit guidance on when to pick this over overlapping siblings like game_projection or injury_consequences. Usage is inferable from the resource list rather than stated.

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