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

With readOnlyHint=true and openWorldHint=true already declaring a safe, live-data read, the description's main added value is the field inventory (mark price, funding yearly, max leverage), which substitutes for the absent output schema. It does not mention latency, refresh cadence, or whether markets with zero volume appear, so it is useful but not fully transparent.

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?

A single tight sentence that front-loads the resource and then packs the returned metrics and the sort/filter controls. Every clause carries information; nothing is repeated from the title.

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 listing tool with no output schema, the enumerated metric list is the essential missing piece and it is present, alongside sort and filter behavior. It stops short of stating result ordering tie-breaks or what an empty filter match returns, which are the remaining gaps.

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 coverage is 100%, so defaults, enum values and the BTC-style coin example are already documented there. The description restates the sort dimensions and the coin filter without adding format details (e.g. whether query is case-sensitive or matches partial tickers), so baseline 3 applies.

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 (perpetual futures markets on Hyperliquid) and enumerates exactly what each entry contains: mark price, 24h change, funding hourly/yearly, open interest, volume, max leverage. It reads clearly as a market-wide listing rather than a single-asset quote, but it never names the closest sibling (perp_quote), so the distinction must be inferred from the plural/catalog framing.

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 by the mention of sorting and coin filtering, which tells the agent this is a screener/ranking call. However, there is no explicit when-to-use-this-vs-perp_quote guidance and no statement about scope (all Hyperliquid perps only, or other venues), leaving the agent to guess the boundary with the quote tool.

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