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

Annotations already declare readOnlyHint=true and openWorldHint=false, so safety is covered; the description adds that the payload spans price history, mandatory/optional extras and photos, which tells the agent how heavy the response is. It omits any note on caching, rate limits, or what happens if a boat-week is no longer discounted.

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?

Two sentences: the first front-loads the purpose and payload contents, the second handles input sourcing. The field enumeration is dense but each item answers whether the call is worth making.

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 an output schema present and full annotation coverage, the description need not explain return values, and the input story is nearly complete. The one gap is that it never states explicitly that at least one of id or url is required, which matters when required=0.

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 100% and both fields carry examples, so the schema does the heavy lifting; the description still adds real value by clarifying that the id is the trailing number of the page URL and that the URL can be passed instead. Since required=0, the 'or' phrasing implicitly signals that one of the two must be supplied, which the schema alone does not state.

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 description opens with a specific scope statement — 'Everything known about one discounted boat-week' — and enumerates the record's contents (prices, price history, specs, extras, photos, other weeks), so an agent knows exactly what it retrieves versus the list-style search_deals. It does not distinguish itself from get_yacht_model or compare_boats, which could plausibly return overlapping spec data.

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?

It names search_deals as the source of the id/URL, which is useful upstream context, but gives no when-to-use/when-not guidance against siblings like compare_boats or is_good_deal. Usage is implied by the scope rather than stated.

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