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

Annotations already cover safety profile (readOnly, idempotent, non-destructive). The description adds two valuable behavioral details: the monetary cost of $0.001 USDC per call and the fact that it is byte-identical to a specific HTTP endpoint. These go beyond annotations and inform the agent about side effects (cost) and implementation fidelity.

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 concise sentences achieve maximum information density: the first states the data contents, the second covers cost and endpoint equivalence. No fluff or redundancy; the most important functional info appears first.

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, single-parameter tool with an output schema and rich annotations, the description is reasonably complete. It covers data content, cost, and endpoint mapping. It does not mention rate limits, data freshness, or error behavior, but these are not critical given the simplicity and the presence of an output schema.

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 fully documents the only parameter 'coin' with a clear description and required flag (100% coverage). The description does not add any additional semantic detail about the parameter beyond what the schema provides, so the baseline score of 3 is appropriate.

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?

The description names the exact resource ('live risk frame Hyperliquid publishes per perp') and enumerates the specific fields it returns (funding, open interest, mark/oracle price, premium, 24h notional volume). This is a precise verb+resource statement that clearly differentiates it from other Hyperliquid market tools like market_hl_mid_price or market_hl_funding_history, which target narrower data slices.

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 description does not explicitly state when to use this tool versus any of the other Hyperliquid siblings (e.g., market_hl_candles, market_hl_order_book, market_hl_perp_specs). It only describes the data contents without giving selection criteria or excluding alternatives, so an agent has no direct guidance on routing.

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