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

Annotations already declare readOnlyHint=true and openWorldHint=true, covering the safety profile. The description adds nothing beyond that: no indication of whether 'locations' means physical storefronts versus online availability, no auth or rate-limit context, and no disclosure of anything not already in structured data.

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?

It is a single short, front-loaded fragment with no padding, so it is not bloated. However, the one sentence is so minimal that it barely earns its place next to the tool name.

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?

An output schema exists, so return values need not be explained, and annotations cover safety. But for a tool whose whole purpose hinges on what 'locations' means for a Shop.app shop, the description leaves that ambiguity unresolved and provides no routing context against the many nearby shop_app_* siblings.

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%, with 'handle' documented as the Shop.app shop handle (e.g. marcnolan) and 'limit' documented with default 10 and maximum 50. The description contributes no additional parameter meaning, 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 'Shop.app shop locations.' merely restates the tool name and resource with no verb describing what operation is performed (list? lookup? availability?). It distinguishes the resource from siblings like shop_app_shop_products or shop_app_shop_reviews, but only because the name already does that work. It reads as a tautology rather than a purpose statement.

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?

There is no guidance on when to use this tool versus shop_app_shop, shop_app_shop_products, or shop_app_shop_reviews, no prerequisites, and no exclusions. The agent must infer usage entirely from the name.

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