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

Annotations already declare readOnlyHint and openWorldHint=false, but the description adds real behavioral context: data is rebuilt every morning, coverage is limited to North American ports and balcony/suite cabins, and negative percentages mean late fares cost more than booking ahead. It does not mention pagination or result volume, but adds meaningful value beyond the annotations.

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 core scope in the first clause and no filler sentences; each sentence carries distinct information (scope, filters, price-delta semantics). Slightly dense but no waste.

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 convey what comes back; it explains that each entry compares the late fare against the book-ahead price for the same ship, grade and length, and that negative values mean a premium. It does not enumerate full return fields, leaving a modest gap.

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 only 33% (only from_port is documented). The description mitigates this by explaining that results can be filtered by departure port or region, giving region implicit meaning, but it adds nothing for 'limit' (default 10, max 25) and gives no format hints for region. Baseline 3 given the partial compensation.

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+scope: a daily report of balcony and suite cabins on cruises departing North American ports within ~21 days, benchmarked against book-ahead prices. This distinguishes it from generic siblings like search_cruises or cruise_options by its narrow inventory and price-delta framing.

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?

'Filter by departure port or region' implies how to narrow results, but there is no explicit when-to-use guidance versus search_cruises or cruise_options, and no stated exclusions. Usage context is implied rather than stated.

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