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

Annotations already declare readOnly, idempotent, openWorld and non-destructive, so the safety profile is covered. The description earns credit by adding that it "never performs a purchase" — important context given it returns purchase links — and by disclosing the return shape (source plus optional purchase links).

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 compact sentences, front-loaded with the identity of the operation and followed by the return/behavioral note. No filler and nothing redundant.

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 usefully covers the return payload and the no-purchase guarantee, and it names both required inputs. Remaining gaps are minor: no explicit sibling routing and no statement of error behavior for an unknown id.

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 0%, so neither parameter is documented in the schema; the description at least establishes that id must be an exact item id and that site scopes the lookup. It does not explain the site enum values or the 1-120 length constraint, so it only partially compensates for the coverage gap.

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 published catalog entry") plus the scoping keys (site and exact item id), and the word "published" narrows scope meaningfully. It implies but never names its sibling search_catalog, so differentiation from the search path is left 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?

"by site and exact item id" hints that a caller needs a known id, which implicitly pushes lookup-by-query toward search_catalog, but no alternative or prerequisite is stated explicitly. Usage is implied rather than prescribed.

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