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

Annotations already declare readOnlyHint, idempotentHint, destructiveHint=false and openWorldHint=false, so safety is covered. The description earns credit by disclosing the shape of the returned guide (intro, activities, season months, callers, airport transfer with route/rentals/ease) when no output schema exists. It does not say what happens when the code is unknown or the guide is missing.

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?

A single dense sentence that front-loads the object ("One port's saved guide") before listing fields; every clause names actual returned data, so nothing is wasted. It is a sentence fragment without a verb, which slightly weakens the structural front-loading.

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 one-parameter read tool with rich annotations and no output schema, the description covers the main gap by enumerating the return contents. Only edge-case behavior (invalid or uncovered port code, empty guide) is left unaddressed.

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% and the property description already explains the five-character UN/LOCODE format and the USPCV/GBSOU examples. The description adds nothing about the code parameter beyond the word "One port's," so the schema carries the full burden.

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 phrase "One port's saved guide" plus an enumeration of contents makes clear this fetches a single port's detail record, which distinguishes it from the list_cruise_ports and list_cruise_port_catalog siblings. It lacks an explicit verb ("get"/"retrieve") so the action is implied by the noun phrase rather than stated.

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?

There is no explicit when-to-use guidance and no named alternative (e.g., "use list_cruise_ports to find a code first"). The singular "one port's" implies it follows a catalog or list call, but the agent must infer that.

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