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

Annotations already declare readOnlyHint=true and openWorldHint=true, yet the description adds real context: public-data-only sourcing, ~3 min refresh cadence, the 'stale data never charged' billing guarantee, and the x402 wallet-payment requirement. This is meaningful disclosure beyond the annotations, though it doesn't describe response shape or clustering thresholds.

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?

Four short sentences, front-loaded with what the data is, then freshness/billing, payment, and disclaimer. Every sentence carries information relevant to a paid data tool, with only the 'Not financial advice' line being borderline boilerplate.

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, two-parameter tool with no output schema, the description covers the data source, scope, freshness, pricing model, and payment mechanics. It omits detail on what 'clustered near the current price' quantitatively means and what the returned structure looks like, but nothing critical to invoking it is missing.

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 parameters (coin, payment_signature) are already fully documented, which sets the baseline at 3. The description implies the per-coin grouping and the payment flow but adds no syntax or format detail beyond the schema.

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 verb+resource: 'exchange-reported liquidation prices of large tracked Hyperliquid accounts clustered near the current price, per coin.' This is clearly distinguishable from generic market data. It does not explicitly route against the close sibling hyperliquid_whale_positioning, so it falls short of a 5.

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?

Usage is implied ('clustered near the current price') and there is a partial workflow hint about omitting payment_signature to receive the live 402 offer. However, there is no explicit when-to-use vs alternatives guidance or when-not guidance relative to hyperliquid_whale_positioning or hyperliquid_funding_extremes.

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