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

Annotations already declare readOnly/idempotent/non-destructive/closed-world, so the safety profile is covered structurally. The description adds real behavioral context beyond that: the tool may return nothing when facts are unpublished, and it disclaims legal advice. It doesn't say how the facts are sourced or aged, which keeps it short of a 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?

Front-loaded with the return payload, then usage, then caveats — a sensible ordering with no filler sentences. It is a dense run-on sentence, but every clause carries distinct information, so it stays efficient rather than bloated.

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 takes on the burden of describing returns and does so by enumerating the fact categories the tool surfaces. Combined with usage triggers and the empty-result caveat, an agent has everything needed to call it correctly.

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 both parameters (handle, language) are documented in the schema itself, including the handle's carry-forward semantics. The description adds nothing about either parameter, so the baseline 3 applies.

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 (returns) plus specific resource (the provider's own statement on booking), with the returned content enumerated: operator identity, agency role, insolvency cover, payment and cancellation terms, legal page links. An agent can distinguish this from ship_profile, cruise_line_profile, and advise without opening any 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?

Explicit when-to-use triggers are given ('whether booking here is safe, who they are contracting with, or how payment is protected'), plus an explicit exclusion ('does NOT give legal advice') and an edge-case behavior ('returns nothing if the provider has not published these facts'). That is when, when-not, and empty-result handling in one pass.

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