run_rakuten_items_reviews

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

No annotations are provided, so the description carries the burden. It usefully discloses the return fields (rating, text, author, dates, helpful count, purpose tags, SKU, media, shop replies) and the cost model ('1 point per returned record'), which is real behavioral value. However it says nothing about auth requirements, rate limits, or pagination behavior beyond what the schema exposes.

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 dense sentence that front-loads the core resource and then enumerates return fields plus cost. Every clause carries information; only the field enumeration is slightly list-heavy. Well sized for the tool's complexity.

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 and no annotations, the description compensates by naming the returned fields and the point cost, which is what an agent needs to decide to call it. Pagination semantics (start_page/max_items interplay) are left to the schema, a minor gap.

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 all three parameters (item, max_items, start_page) are already documented. The description's 'by shop_code/item_code or URL' mirrors the schema's item description rather than adding new meaning. Baseline 3 is appropriate when the schema does the heavy lifting.

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+resource: 'Customer reviews of a Rakuten Ichiba item,' and lists the fields returned, so an agent can distinguish it from run_rakuten_items or run_rakuten_items_search. It does not explicitly name those siblings, but the 'reviews' framing makes the scope 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?

Usage is implied by the description (fetch reviews for a given item), but there is no explicit when-to-use vs when-not guidance and no alternative named among the many review tools (run_newegg_products_reviews, run_walmart_product_reviews, etc.) or the sibling run_rakuten_shops_items. Adequate but leaves routing to inference.

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