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

Annotations already declare readOnlyHint=true and openWorldHint=true, so the safety profile is covered. The description adds little behavioral context beyond that - no pagination limits, total-count behavior, or sort order - so with the lower bar set by annotations, a 3 is appropriate.

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?

Three short, front-loaded sentences with no filler; the core purpose leads and the sibling routing closes. The param restatements are minor duplication of the schema but not wasteful enough to drop below 4.

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 an output schema present the return values need no explanation, and annotations cover safety. The description is complete enough to invoke correctly, though it omits whether more than 14 reviews are reachable or how ordering works.

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 schema already documents id, limit (default 14), and offset. The description repeats these meanings verbatim and adds no syntax, format, or edge-case detail beyond what the schema provides, matching the baseline 3.

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 ('Returns buyer reviews for an Etsy shop') and explicitly names the sibling it is not ('etsy_listing_reviews'), so an agent can distinguish shop-level from listing-level reviews without inspecting either schema.

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 closing sentence routes the agent to the correct alternative ('Use etsy_listing_reviews to get Etsy listing reviews'), giving clear context for choosing this tool over its sibling. It does not state explicit when-not conditions or prerequisites, so it falls 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.