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

Annotations only declare readOnlyHint; the description usefully adds that shopID 0 returns aggregate all-shops records rather than a real shop, and that next_url drives pagination. It omits any note on default page size or how totals behave across shops, but the added behavioral context is real.

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 tight sentences, front-loaded with the resource and its records, then the shopID-0 caveat, then pagination and endpoint. The field list earns its place because there is no output schema, though it is slightly dense.

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 8 optional parameters, no output schema, and minimal annotations, the description covers the essentials: record shape/fields, the aggregate-shop special case, and pagination. It leaves the exact response envelope and total-count behavior unspecified, a minor gap given the field enumeration.

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 parameters are already well documented. The description reinforces the shopID 0 and next_url semantics, which is genuinely helpful, but adds nothing about min_qoh/max_qoh or modified_since beyond what the schema states.

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: stock levels per item per shop as ItemShop records, enumerating the fields returned. This distinguishes it from sibling list_items and list_shops by scope (per-item-per-shop quantities), though it never names an alternative explicitly.

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?

Gives practical guidance on two things: shopID 0 means the all-shops summary and paging uses next_url. It does not say when to prefer this over list_items/list_shops or when a filter (e.g., min_qoh) is the right approach, so usage is implied rather than stated.

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