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

Annotations already declare readOnlyHint, idempotentHint, destructiveHint=false and openWorldHint=false, so the safety profile is fully covered elsewhere. The description adds one genuinely new behavioral fact — availability is only returned 'when displayed by this storefront' — but says nothing about partial matches, missing products, or error behavior for a batch lookup.

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 with no filler; the constraint and the return contract come before any elaboration. It is compact and readable, though the batching limit overlaps with structured schema data.

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?

For a read-only lookup with no output schema, the description does state the shape of the result, which is important. It stops short on the language parameter's effect on returned values and on how missing or non-displayed products surface in the response.

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 the description must carry the load. It explains the products array as 1–20 exact IDs or SKUs and gives 'this storefront' meaning to the storefront parameter, but the language parameter (12-value enum) is completely unmentioned and the 20-item cap merely restates maxItems already in the schema.

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 ('Look up ... exact product IDs or SKUs') and pins the scope with 'exact', which distinguishes it from the sibling search_products without naming it. The return payload (public MSRP, indicative availability) is also named, making the tool's identity unambiguous.

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?

The word 'exact' implies this is the tool for known identifiers rather than discovery, which is usable guidance. However, it never states when to prefer search_products instead, nor what happens when an ID is unknown or unavailable in the given storefront — usage is implied rather than spelled out.

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