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

Annotations already declare readOnly, idempotent, non-destructive and closed-world, so the safety profile is covered. The description still adds real context beyond them: that each store was separately approved in its own Shopify admin (an authorization dependency the agent could otherwise trip over) and that a default exists. It does not describe the returned fields, but with no output schema and a trivial read this is a minor gap.

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?

Two sentences, no filler, with the returned content first and the actionable follow-up second. Every clause carries information an agent needs.

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?

For a no-parameter, no-output-schema read tool this is close to sufficient: it says what is returned and how to use it. The only shortfall is not indicating the shape of the returned store identifiers, which the agent needs in order to pass `store` correctly to sibling tools.

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?

Zero parameters, so the schema does no work and the baseline is 4. The description goes slightly further by explaining the related `store` argument on other tools, though it never says what form that value takes (name vs id), which is the one piece of meaning the agent still has to infer.

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?

Names the specific resource (the Shopify stores available to this connection) and adds the salient attribute returned (which one is the default). It is distinguishable from siblings like list_apps or list_items by resource, though it never states that differentiation 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?

The second sentence gives concrete downstream guidance: pass `store` to any other tool to act on a different store. That tells the agent why to call this. It stops short of stating when NOT to call it or naming an alternative source for store info (e.g. get_setup).

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