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

With no annotations, the description carries the behavioral burden. It explicitly says 'Read', signaling a safe read-only operation, and explains meaningful output semantics such as claim_price being 'the exact USDC that takes it' and quiet_since being 'null if never'. This is sufficient transparency for a read-only leaderboard tool.

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 description is front-loaded with the core action, then delivers dense but relevant return-value semantics, and ends with a practical usage instruction. Every sentence contributes useful information; there is no filler or repetition of schema content.

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 read-only tool with no output schema and no annotations, the description covers the key output fields, their meaning, and how to personalize results. It does not explicitly state the behavior when category is omitted, but this is a minor gap given the clear leaderboard context and optional parameters.

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?

The schema already documents both parameters at 100% coverage, so the baseline is 3. The description adds value beyond the schema by explaining that agent personalizes prices based on what the caller has already spent, and clarifying that category maps to per-category crown data.

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 opens with a specific verb and resource: 'Read the Agent Arena leaderboard.' It further distinguishes the tool by enumerating what it returns — every rank, claim_price, crowns, cheapest_crown, and quiet_since — which clearly separates it from sibling tools like arena_feed or arena_clash.

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 context is clear: use this to read the leaderboard, inspect crown prices, and check whether crowns are still defended via quiet_since. It also instructs the caller to pass an agent name to personalize prices. It does not explicitly name alternatives or state when not to use it, but the read-only leaderboard purpose is unambiguous.

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