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

Annotations already declare readOnly/idempotent/closed-world, so the safety profile is covered. The description adds non-obvious behavior beyond that: the default no-date behavior restricts results to today onward, and turnaround days embed a ride_to_pier object with a prefilled booking link and quote_ride_arguments. No output schema exists, so it would benefit from slightly more on the shape of returned records (e.g. what fields exist for non-turnaround days).

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 purpose, then filtering, then the cross-tool workflow, then the default-date caveat. Sentences are information-dense with no filler; the only mild cost is that several ideas are packed into long parenthetical clauses.

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, 6-param, all-optional query tool with no output schema and no nested objects, the description covers what it returns (pier/terminal, ships per day, ride_to_pier booking data) and the default date behavior. A little more on the response structure would make it fully 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?

Schema description coverage is 100% with per-parameter descriptions and an enum for pier, so the schema already does the heavy lifting. The description restates the filter set and adds the fuzzy-matching hint for ship, but that hint is also in the schema, so little value is added beyond it.

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?

Specific verb+resource: 'Look up Seattle cruise sailings from the Port of Seattle schedule', with the exact queryable facts (pier/terminal per date, ships per day) and season scope (2026 + preliminary 2027). It is clearly distinct from siblings like quote_ride, which it names as a downstream step.

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?

Gives concrete filter dimensions (ship fuzzy, cruise_line, date or from/to, pier) and a clear hand-off rule: call quote_ride with quote_ride_arguments plus a pickup time for the live fare. Also states the implicit default ('without a date filter, only sailings from today on are returned'), which governs when a date filter is needed. No explicit 'do not use this for X' exclusion, keeping it at 4.

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