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

Goes well beyond the readOnlyHint/openWorldHint annotations: it discloses the large source file and slow first call after a cache miss, a $0.002 per-successful-call charge, the x402 payment rails (Base, Solana, Arc), and that failed calls are not charged. Cost and latency are exactly the operational facts an agent needs before invoking.

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?

Three sentences, front-loaded with what the tool returns, followed by data-quality caveat and then cost/latency. Every sentence carries distinct information; no filler or repetition of the name.

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 an output schema present, return-value structure need not be described, and the description covers the remaining gaps an agent would care about: data nature (public, addresses only), performance characteristics, and payment mechanics. Nothing material is missing for correct invocation.

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%, with both parameters already documented including defaults, so the baseline is 3. The description restates the window values and adds context that rows are 'top accounts', but says nothing about the limit parameter or its range, so it adds little 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 resource and verb: 'Hyperliquid public trader leaderboard: top accounts ranked by PnL' and enumerates the returned metrics (account value, ROI, traded volume). The domain is unmistakable against siblings like b2b_openllm_leaderboard and b2b_pgatour_leaderboard, which are different datasets entirely.

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?

Clearly frames the tool as a public on-chain stats lookup with selectable windows, and notes addresses only / no names, which sets expectations for what the agent will get. It does not explicitly name when to prefer a sibling or what to do when a query needs named traders, but the use case is unambiguous. Pricing and first-call latency also inform when to call it.

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