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

Annotations already declare readOnly, openWorld and non-idempotent, and the description adds real substance beyond them: the cohort definition (120 most profitable accounts by 30-day PnL from the public leaderboard), that results reflect 'right now' with a reported snapshot age and coverage, and an explicit 'read-only analytics; not financial advice' caveat. It doesn't state rate limits, caching or failure modes, so 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?

Front-loaded with the user-level question followed immediately by what is returned, then the free-vs-paid boundary. The tail of paid endpoint enumeration is somewhat promotional but does carry routing information, so it earns most of its space.

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 does the work by enumerating the return fields (bias category, cohort long vs short counts, snapshot age, coverage) and by labeling the tier. Missing only latency, refresh cadence/coverage thresholds and error behavior for an unrecognized ticker.

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 the single `symbol` parameter at 100% coverage, including accepted ticker variants, and the description only restates that it takes a Hyperliquid perp ticker. With full schema coverage and one required param, the baseline 3 applies; the description adds no new parameter meaning.

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 question-and-answer: returns how the top-120 profitable Hyperliquid cohort is positioned (long/short bias plus cohort counts) for a given perp ticker. It also separates the free preview from the paid x402 routes, so the agent knows exactly what this tool answers and what it doesn't.

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?

Clear context: use for a Hyperliquid perp ticker to get directional cohort bias; if the agent needs notional, 1h/24h flows, entries, leverage, liquidation clusters, scan, or wallet profiles, the description routes those to the named /v1/lite, /v1/coin, /v1/scan and /v1/wallet endpoints. No explicit when-not-to-use or error/precondition guidance, so it stops 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.