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

With readOnlyHint/idempotentHint/destructiveHint already provided, the description adds valuable behavioral semantics: point-in-time reads, rank 0 as champion, movement vs previous snapshot, is_new for debuts, and meta containing previous/next snapshot dates. No contradiction with annotations.

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?

Three dense sentences, with the core purpose and point-in-time nature front-loaded. No filler; every clause contributes distinct information. A model of conciseness.

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?

Given there is no output schema, the description supplies key output semantics (entry movement, is_new, meta snapshot dates) and parameter behavior. It doesn't spell out the exact response envelope or pagination, but for a read-only fetching tool 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 already documents all 4 parameters (100% coverage), so baseline is 3. The description adds meaning beyond the schema: the date parameter is for point-in-time reads, division narrows the board, and board defaults to official. This elevates it to 4.

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 states a specific verb+resource: reading the official rankings board for one promotion, with point-in-time semantics. It distinguishes this from generic leaderboards or champion lists by emphasizing 'official rankings board' and historical date reads. The title and description align.

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 clearly frames when to use the tool: when you need the official rankings board for a promotion, optionally as of a specific date and narrowed by division. It does not explicitly name sibling alternatives like get_leaderboard or get_champions, so it misses the exclusionary guidance for a 5, but the context is unambiguous.

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