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

With no annotations, the description carries the full burden and does well: it reveals the auth path (X-API-Key header or api_key param) and the plan-dependent history limits, which the agent cannot infer elsewhere. It omits error behavior (e.g., invalid address) and pagination of snapshots, keeping it short of a 5.

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 account/address scope, then the returned fields, then the auth/history caveats. One dense sentence plus a second, with no filler, though the bracketed '[measured]' tag and the triple-tier history clause make it slightly heavy.

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 2-param tool with no annotations and no output schema, it covers the essentials: what is returned (live positions with detailed fields), where data comes from, and how auth/history depth works. Missing only edge-case/error behavior and snapshot pagination detail.

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 0%, so the description must compensate. It clarifies the api_key parameter's fallback to the connection's X-API-Key header, which is genuinely useful, but adds almost nothing about the required `address` format beyond 'by address'.

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 ('One Hyperliquid account by address') and enumerates exactly what is returned (positions, account value, archived snapshots). It is clearly distinguishable from siblings like get_hl_whales or get_hl_liquidation_map without opening any schema.

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?

It discloses the history-depth tiers (24h free, 31 days Pro, full history on Bot), which implies when a paid key is needed, but it never names an alternative tool or states when NOT to use it versus related siblings. Usage is implied rather than instructed.

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