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

Annotations already declare readOnlyHint, idempotentHint, destructiveHint=false and closed-world, so safety is covered. The description adds real context beyond that: results are priced on both sides per source, include live result and settlement, and player_prop payloads can be large — a useful cost warning for an agent planning calls.

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 sentences, zero filler. The core capability is front-loaded, and the narrowing advice follows immediately, so an agent reading only the first clause already knows what the tool returns.

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 carries the burden of describing the return: per-source two-sided pricing plus live result and settlement is a fair sketch of the shape. It stops short of saying how sources are keyed or how large an unfiltered player_prop result typically is, but for a read-only lookup with four annotations this is close to complete.

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 80%, so the baseline is 3. The description goes beyond the schema by explaining the intent behind marketType (shrinking the result set) and the combination rule for playerId/definitionId under player_prop, which the schema lists but does not motivate.

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+resource (current odds for one game) and enumerates the market types returned: moneyline, spread, total, player props, plus live result and settlement. An agent can distinguish it from game-data siblings like aura_game_frame or aura_boxscore, though it never names aura_odds_timeline, the closest neighbor, so the differentiation is incomplete.

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 second sentence gives operational guidance — pass marketType to keep results small, and add playerId or definitionId when querying player_prop — but this is about narrowing output, not about when to choose this tool over aura_odds_timeline or aura_get_game. Usage is implied rather than stated, and there are no exclusions.

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