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

Annotations already declare readOnlyHint=true, idempotentHint=true, and destructiveHint=false, covering the safety profile. The description adds that it operates on the 'live store' and returns alt text/URLs, but does not disclose additional behavioral traits such as pagination, ordering, or auth requirements beyond what annotations imply.

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 first two sentences are purposeful, but the final 'Routing: Shopify file library: uploaded images/files (alt/url) from the live store' line is largely redundant with the opening sentence and adds little new information. The description is compact but contains some 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?

For a simple read-only list tool with only two well-documented parameters and full annotation coverage, the description is adequate. It explains the purpose, the relevant use case, and the returned fields (alt text and URL), though it does not detail the output shape or pagination behavior.

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 input schema provides 100% coverage for both parameters: limit and companyId. The description adds no parameter-specific meaning beyond the schema, so it earns the baseline score for schema-heavy documentation.

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 clearly states the verb and resource: 'List media files (images and generic files) uploaded to the connected Shopify store's file library' and specifies the return fields 'alt text and URL.' This distinguishes it from sibling tools like list_shopify_content or list_shopify_products by scoping to the file library.

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 description provides an explicit use case: 'Use to find an existing uploaded asset before uploading a duplicate or referencing one in content.' It gives clear context for when to invoke the tool, though it does not explicitly name alternative tools or conditions to avoid using it.

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