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

Annotations already declare readOnlyHint=true and openWorldHint=true, so the safety and network profile are covered. The description's only added behavioral note is that the profile is 'public', which modestly implies no authentication is needed but says nothing about rate limits, caching, or data freshness.

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 sentences, front-loaded with the core purpose, followed by the required parameter and the alternative tool. No filler or repetition.

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 one fully-documented parameter, declarative annotations, and a dedicated output schema, the description covers everything an agent needs to invoke the tool. It could note handle format constraints (e.g., case sensitivity or URL-form input), but that is 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% and the description essentially restates the schema ('handle: Required. Shop.app shop handle, e.g. marcnolan.'). The example handle is mildly helpful but adds no semantics beyond the schema, so the baseline 3 is correct.

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 public Shop.app merchant profile details'), which pins down both the operation and the entity type. It also names the sibling tool shop_app_shop_products, so an agent can distinguish this profile lookup from product listing without opening 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 explicitly routes the agent to shop_app_shop_products when products are wanted, implying this tool is for shop-level profile data only. It gives clear context but no explicit negative condition (e.g., when this tool should not be used on non-Shop.app handles).

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