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

Annotations already declare readOnlyHint=true and openWorldHint=false, so safety and scope are covered structurally. The description adds useful context that the record includes live commercial data ('current price and stock on tasters.ch'), but says nothing about what happens with an unknown or stale ref, or whether locale affects availability of the price/stock fields beyond the schema's own note.

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 front-loaded sentence that opens with the verb-plus-scope and then lists return content; every clause carries information. The enumerated field list is slightly long but each item tells the agent something it would not otherwise know without an output schema.

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 only two parameters, full schema coverage, and no output schema, the description's return-field enumeration does the work the missing output schema would have done. The remaining gap is operational: no guidance on invalid/stale refs or on how price and stock availability vary by locale.

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 both `ref` and `locale` documented in-schema, including the locale-specific-ref caveat. The description itself adds no meaning beyond those field definitions, so the baseline of 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?

States a specific verb and resource ('Full details of one wine') and enumerates the returned content (producer, origin, grapes, ratings, tasting notes, pairings, price and stock), which separates it from the list-oriented `search` sibling. It stops short of naming that sibling explicitly, so the differentiation is inferred rather than declared.

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 when-to-use or when-not-to-use guidance in the description; the reader must infer that this is a follow-up call after a search. Alternatives such as `search`, `recommend_wines`, or `get_pairing` are neither named nor excluded, so the choice between them is left to the agent.

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