run_rakuten_items

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

With no annotations, the description carries the full burden. It genuinely adds value by disclosing the cost model ('Flat 5 points per successful run') and sketching the response payload. It does not cover failure behavior, auth requirements, rate limits, or what happens when the identifier is not found.

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 with the resource lookup front-loaded and cost trailing. The field enumeration is long but each item is informative. No filler sentences.

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 correctly compensates by enumerating the returned fields (price range, subscription price, points, shipping, images, rating, category, shop, SKU variants), plus the cost per run. For a one-parameter detail tool this is close to sufficient, though error/edge behavior is unaddressed.

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 'item' parameter already documents the shop_code/item_code format with an example. The description reinforces the same accepted format (shop_code/item_code or URL) but adds no syntax or edge-case detail beyond the schema. 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?

States a specific verb (Get) and resource (one Rakuten Ichiba item), and enumerates the fields returned (price, points, shipping, rating, SKU variants), so an agent immediately knows this is a single-item detail lookup. It does not explicitly name the sibling run_rakuten_items_search, but 'one item' strongly implies detail vs. search.

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 phrase 'by shop_code/item_code or URL' implies the tool is used when you already hold a specific item identifier, which is meaningful usage context. However, it never states when to use this vs. run_rakuten_items_search or run_rakuten_shops_items, nor any prerequisites. Usage is implied rather than prescribed.

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