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

Annotations already declare readOnlyHint and openWorldHint, so the description's added value is the cost model: $0.002 USDC per successful call via x402 on Base/Solana/Arc, with failed calls not charged. It also discloses the empty-list return when no storm is active. Missing only things like rate limits or data freshness cadence.

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?

One front-loaded sentence covers source and payload, followed by short clauses for the empty case, the category disambiguation, and pricing. Every sentence carries distinct information with no repetition of the title.

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?

An output schema exists, so the returned-field list is a bonus rather than a necessity; the pricing and empty-result behavior are the parts that matter and both are present. A note on data freshness/refresh cadence would make it complete.

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?

Zero parameters, so the baseline is 4; the description correctly implies no inputs are required and doesn't waste space documenting nonexistent arguments.

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?

Names a specific verb+resource (active tropical cyclones from the NHC CurrentStorms.json feed) and enumerates the returned fields. It also pre-empts the category confusion with 'Not a real-estate dataset', so an agent can tell it apart from the surrounding realestate_* siblings without opening the 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?

The context is clear (live/active storms only) and it explicitly excludes real-estate queries, which is real guidance given the tool's placement among property siblings. It doesn't need to name an alternative because no sibling covers hurricanes, but it also doesn't state when NOT to call it beyond the dataset caveat.

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