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

Annotations already cover safety (readOnlyHint, openWorldHint), and the description adds the 30-day lookback window and the concrete metric set returned, which the annotations say nothing about. It doesn't mention cost, rate limits, or what happens when an address has no activity, so it earns a 4 rather than 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?

Two sentences, front-loaded with what the tool returns and finished with how to call it. The long parenthetical label and metric lists are dense but genuinely informative since the agent learns the taxonomy without opening the schema; they cost it the top score.

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 an output schema present, a fully documented 5-parameter schema, and annotations covering the safety profile, the remaining description burden is scope and time window, both of which are stated. Only the sibling disambiguation 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 description coverage is 100%, so every parameter is already documented, giving a baseline of 3. The description reinforces the addresses-vs-label switch but adds no syntax, format, or default detail beyond what the schema already states (e.g. the 50-address cap and max 100 limit live only in the schema).

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 resource precisely: Hyperliquid wallet trading behavior over the last 30 days, enumerating both the label taxonomy and the underlying metrics. An agent immediately knows what comes back. It stops short of a 5 because a sibling named get_wallet_labels exists and the description never says how these two differ.

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?

'Look up specific addresses, or list wallets with one label' cleanly states the two invocation modes and the condition selecting each, which is real routing guidance. It gives no exclusion or redirect toward get_wallet_labels or get_trader_profile, so the agent must infer sibling boundaries on its own.

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