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

Annotations already declare read-only, idempotent, non-destructive and closed-world, so the safety profile is covered. The description adds value beyond that by disclosing the payload semantics: ratings on a 0..1 scale, a rating source, a trust label, and a separate group of shops still waiting for their feed. It does not mention pagination or result size, a minor gap.

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 tight sentences with zero filler, front-loading the returned data and then the questions it answers. The opening is a noun phrase rather than a verb phrase, which slightly slows comprehension, but nothing is wasteful.

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?

There is no output schema, so the description must carry return-value disclosure, and it does: it names the rating range, rating source, trust label and the pending-feed shops. Combined with a fully documented optional parameter and complete annotations, an agent has what it needs; only ordering/count behavior is unstated.

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% and the single country parameter is fully documented as an optional ISO 3166-1 alpha-2 code normally derived from the address. The description only echoes 'for a delivery country' and adds no format or fallback detail, so the baseline 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?

The description states concretely what the tool returns: shops whose prices flow today for a delivery country, their rating (0..1), rating source and trust label, plus shops still awaiting a feed. That is a specific resource with a clear scope. It does not explicitly distinguish itself from near-siblings such as list_my_shops or get_shop_statistics, which keeps it at 4 rather than 5.

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 gives concrete question-shaped triggers: 'can I trust shop X' and 'do you compare shop Y'. That is clear usage context. It stops short of exclusions or naming alternatives (e.g., use list_my_shops for your own registered shops), so no 5.

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