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

Annotations only declare it as a read-only, idempotent, open-world call; the description goes well beyond that by stating that no payment field joins the ranking, that paying cannot improve standing, and that a wallet with a record but no opt-in is omitted entirely rather than shown. These are meaningful behavioral guarantees an agent could not infer from the 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?

The ranking axes and opt-in rule are front-loaded well, but the paid-vs-free point is made three times ("FREE", "paying more cannot move you up", "No payment required"), which is redundant rather than additive.

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?

An output schema exists, so return structure need not be described, and the eligibility/ranking model is well covered. The main residual gap is any hint about limit behaviour or default result size for a board capped at 200.

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 0%, so the description must carry parameter meaning, yet it only echoes the enum values already present for sort (adding that XP is the default, which the schema lacks) and track. The limit parameter, its 1–200 range, and any pagination semantics are never mentioned.

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 resource (the public arena leaderboard over opted-in players) with its scope and ranking axes (XP default, accuracy, streak) and tracks (human/agent). This is clearly distinguishable from sibling arena tools like profile, levels, season, and quests, which cover different concerns.

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 establishes clear eligibility context — free, public, and only opted-in wallets appear — so an agent knows the preconditions before calling. It does not, however, name alternatives or a when-not condition relative to the sibling arena tools, so exclusions are absent.

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