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

Annotations already establish readOnly/idempotent/non-destructive behavior. The description adds operational context beyond annotations: role values, the expected_updated_at handoff to theme publish, and the live-vs-draft caution. This is useful behavioral detail for a read-only list tool.

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?

The core information is front-loaded and the description is compact. The final 'Routing:' line is somewhat redundant with the opening sentence but adds the useful 'MAIN (live)' clarification, so it earns its place.

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 simple one-parameter read-only list with no output schema, the description covers what the tool returns, how to pass updatedAt onward, and when to call it. Nothing essential is missing for correct selection and invocation.

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?

The only parameter, companyId, is already fully described in the schema (100% coverage). The description does not need to add parameter semantics but also does not add any beyond mentioning the connected store context.

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 opens with a specific verb and resource ('List themes installed on the connected Shopify store') and enumerates the returned fields (name, role, updatedAt). It also clarifies the MAIN/unpublished/development distinction, which separates this listing tool from file/content-oriented Shopify tools.

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?

It states a clear precondition: use before reading or editing a theme file so the agent targets the live theme rather than a draft or archived one. It does not name alternative tools or give explicit when-not-to-use cases, but the usage context is unambiguous.

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