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

Annotations already establish readOnly, idempotent, closed-world and non-destructive, so the safety bar is covered. The description adds genuinely useful context beyond them: what the composite score is built from and the anti-vanity framing that tells the agent the ordering is not raw P&L. It does not mention pagination or result freshness, hence not a 5.

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 dense sentences, front-loaded with the ranking concept, then the signal inputs, then the returned fields, then the use case. No filler and nothing buried.

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 correctly carries the burden of naming the returned fields (rank, composite score, identity, P&L, win-rate, volume). What is missing is how the preset parameter selects among rankings and where to discover valid preset ids, a real gap for a ranking tool with many ranking-related siblings.

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 both limit (max 25) and preset (default 'polyrank-default', calibration-heavy) are already documented. The description adds no syntax or semantics for either parameter, so baseline 3 is correct.

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?

Names a specific verb and resource ('top Polymarket traders ranked by genuine SKILL') and pins down the ranking methodology (Brier/calibration, alpha-vs-mid, risk-adjusted return) as opposed to P&L or win-rate rankings. It does not name a sibling tool, so the agent must infer the difference from polyrank_rank_wallets or polyrank_get_custom_ranking itself.

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 closing clause 'Use it to find traders to study' gives one concrete use case, which is more than nothing. But there is no when-not guidance, no mention of the preset alternative (polyrank_get_custom_ranking / polyrank_list_ranking_templates), and no prerequisites such as whether a preset must exist first.

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