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

With no annotations, the description carries the burden and mostly succeeds: it discloses the data source (live from Hyperliquid), freshness (cached 2 minutes), the OI convention (one side), and that it takes no arguments. It lacks any statement on auth/rate limits, but for a public read endpoint that is a minor gap.

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?

Front-loaded with the purpose and scope, then the return fields, then the sibling exclusion and caching note. Dense but every clause is informative; slightly telegraphic ('one side') but not padded.

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?

No output schema exists, but the description enumerates the returned fields (markets as dex:COIN, open interest USD, 24h volume, mark price, hourly funding and APR), so an agent knows what to expect. Complete for a zero-argument read tool.

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 tool takes zero parameters, so the baseline is 4. The description reinforces this explicitly with 'No arguments,' which is more than the empty schema says.

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 (perp markets deployed by third parties on Hyperliquid) and gives concrete examples (xyz:SP500, xyz:GOLD). Explicitly distinguishes itself from siblings get_open_interest and get_funding_rates, which it says cover Hyperliquid's own crypto listing.

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?

Names the alternatives (get_open_interest, get_funding_rates) and the exact condition that selects this tool instead: HIP-3 builder dex markets such as equities, commodities and pre-IPO names. No inference required for routing.

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