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

Annotations only cover the read-only, closed-world safety profile; the description adds genuinely new behavioral facts: a cost of 5 credits, the exact metrics returned (GSAX, high-danger save%, rolling 10-game save%/GSAX, form trend, rest days), and a data-coverage nuance that goalie xG spans all strengths unlike the 5v5-only team possession columns.

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 usage trigger is front-loaded in the first clause, followed by a dense but tightly packed enumeration of outputs and the cost line. It is run-on in places but nearly every phrase carries information.

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 six-parameter, zero-required leaderboard tool with an output schema and read-only annotations, the description covers when to call it, what it returns, the nuance around xG coverage, and the credit cost. Nothing needed for correct invocation is missing.

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 all six parameters including defaults and enum values. The description's 'sorted by save%, GAA, GSAX, or wins, with a games-played filter' largely restates sort_by and min_games rather than adding syntax or edge-case guidance, so 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?

The description names a specific verb and resource ('ranking goalies', 'goalie leaderboard') and states the sort metrics, which cleanly separates it from the skater-oriented siblings (get_player_stats, get_skater_season_stats). An agent can select it without opening the schema.

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?

It gives a clear trigger condition ('Use when ranking goalies or comparing goalie performance') and implies the games-played filter context. It does not explicitly name an alternative tool or a when-not-to-use case, so it falls short of a 5.

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