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

Annotations already declare readOnlyHint=true and openWorldHint=true, so the description's job is to add context, and it does: it discloses the stats window (30-day headline, 90-day in stats.d90), the metrics (pnlUsd, pnlPct), and the scope limitation (perps only). This is meaningful disclosure beyond the structured fields.

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 dense sentence that front-loads the three returned artifacts and only then qualifies the stats window. No filler, though the sentence is somewhat clause-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?

With no output schema, the description must hint at return shape, and it does by naming the stats.d90 nested field and its metrics, plus the perps-only scope. It leaves pagination and exact equity/position field names unstated, but the essentials are covered for a read-only lookup.

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% and the single address parameter is fully documented with a pattern, so the schema does the heavy lifting. The description adds only a light hint that the address is the leader's rather than the caller's, which is helpful but marginal.

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 concrete outputs (equity, open positions, statistics) for a specific resource (a Hyperliquid leader address), which distinguishes it from get_leader_positions and get_account. It lacks an explicit framing verb like 'fetch', but the content is specific and identifiable.

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?

There is no explicit when-to-use statement or named alternative; the phrase 'an address you could copy' only implies this is a copy-trading research call. An agent must infer that get_leader_positions is the narrower sibling and backtest_leader the simulation counterpart.

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