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

Annotations already declare readOnlyHint and openWorldHint, so safety is covered; the description adds a genuinely non-obvious data-semantics rule that isn't in any structured field — that basket-total history must never be conflated with product history. It stops short of describing pagination, auth, or rate behavior, but the caveat is real added value.

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, zero filler, with the primary action front-loaded and the constraining caveat second. Nothing repeats the title or the structured fields.

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?

An output schema exists, so return-shape explanation is not required, yet the description usefully names the three things returned (catalogue data, offers, history) and flags their conditional availability. The only real gap is the undocumented product_id format, which is a minor omission for a one-parameter tool with an output schema.

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?

The schema has 0% description coverage on the single product_id parameter (maxLength 80), so the description must carry the burden and largely does not. 'Catalogue product' weakly hints the ID is catalogue-scoped rather than store-scoped, but no format, prefix, or source for the identifier is given.

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 ('Get a catalogue product') and enumerates the payload ('observed store offers and product history'), which separates it from search_products by implying lookup rather than discovery. It does not name any sibling explicitly, so differentiation is left partly to inference.

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?

Usage is implied by the single required product_id — an agent can infer this is the retrieval-by-identifier tool while search_products handles discovery — but no when-to-use, when-not, or alternative tool is named. The phrase 'where available' softly signals partial results without explaining when data will be missing.

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