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

Beyond the readOnly/idempotent annotations, the description discloses pricing ($0.01), that unknown symbols or unavailable data return an error with no charge, that OI-change components are null until snapshots cover the window, and that it returns x402 payment requirements. It also clarifies the output is factual checks only with no buy/sell recommendation.

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?

The description front-loads price and purpose, then enumerates the return components — justified because there is no output schema. It is dense and run-on, but almost every clause contributes specific information rather than filler.

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 carries the burden of explaining return values and does so thoroughly: summary string, venue comparisons, funding detail and rank, OI deltas with null semantics, sentiment, as_of timestamps, and flag rules. It also covers payment and error behavior and links a free sample response.

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?

There is only one parameter and the schema description already covers it fully (Hyperliquid perp ticker, including dex:TICKER format). The description adds no extra symbol syntax or edge-case guidance beyond what the schema provides, so the baseline 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 clearly states a specific verb and resource: a pre-trade preflight for one Hyperliquid perp that returns a defined bundle of metrics in one call. It distinguishes itself by scope and aggregation, but never names sibling tools (e.g., get_perps_context or get_price) that an agent might otherwise choose, so sibling differentiation is only implicit.

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 'pre-trade preflight' framing gives a clear usage context, and 'in one call' implies this replaces multiple narrower lookups. However, it does not explicitly say when not to use it or name alternatives, so the guidance stops short of full when/when-not routing.

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