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

Beyond the annotations (which only cover the read-only/idempotent safety profile), the description discloses three operationally critical traits: refresh cadence (every 5 minutes), failure behavior (stale data answers 503), and cost (0.02 USDC per call via x402 on five named chains). These are exactly the details an agent needs to plan a paid, freshness-sensitive call.

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?

It is front-loaded with the trigger condition, then the return payload, then the coin-specific behavior, then the refresh/cost logistics. Every sentence carries distinct information with no filler or repetition of the schema.

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, idempotent, paid data tool with an output schema already defining return shape, the description covers purpose, trigger, the coin-mode behavioral difference, freshness, error behavior, and cost. Nothing an agent needs to invoke it correctly is missing.

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%, so the schema already documents both parameters and the baseline is 3. The description adds real meaning beyond it by explaining the behavioral effect of coin (adding liquidation bands and the largest positions), which is not captured in the schema's terse field description.

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 gives a specific verb and resource: it 'returns the open perp positions of the largest Hyperliquid accounts aggregated per coin,' then enumerates the exact metrics (net long/short USD, account counts, size-weighted entries, distance to liquidation, uPnL). This is specific enough to distinguish it from the many generic positioning and liquidation siblings like get_positioning or get_liq_heatmap.

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 opens with an explicit trigger condition ('Use when an agent needs to know how the biggest Hyperliquid traders are positioned'), which clearly frames the use context. However, it names no alternatives or exclusions, so an agent choosing between this and other Hyperliquid/positioning tools gets no routing guidance.

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