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

Annotations already cover read-only, idempotent, and non-destructive behavior. The description adds useful behavioral context beyond that: the quote reflects the exact checkout shipping tier and any running promotion, quantity is expressed by repeating a SKU, and a checkoutUrl is included. It does not detail edge cases like invalid SKUs, but that is acceptable given the annotation coverage.

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?

The description is front-loaded with the exact question it answers and then lists the output components in a compact, scannable sentence. Every clause earns its place; there is no filler or redundant restatement of the tool name or title.

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 simple two-parameter, read-only tool, it explains the main output fields, delivery scope, and quantity convention, which compensates for the missing output schema. A 5 would require more precision about the response shape or failure behavior, but the key information needed to call it correctly is present.

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%, so the baseline applies. The description repeats the schema's 'repeat a SKU' guidance and adds the EU-country scope, but it does not meaningfully enrich parameter semantics beyond what the input schema already documents.

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 the exact user-facing question it answers and enumerates the output components: items, exact checkout shipping tier, running promotion, total in EUR, and checkoutUrl. This clearly separates it from siblings like get_product, search_products, and store_info, which do not provide all-in delivered pricing.

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 provides a clear trigger condition: use this when the user asks 'what does this cost in total, delivered?' and sets an explicit scope of the 27 EU countries. It does not explicitly name an alternative tool or state when not to use it, so it stops short of a 5.

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