list_metafield_definitions

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

No annotations are provided, so the description carries full burden. It indicates a read-only listing operation (implied by 'List') and mentions 'via GraphQL', but does not disclose pagination, rate limits, permissions, or any side effects. The description adds some context (store-level scope) but falls short of full transparency.

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 description is two concise sentences: first states purpose, second lists return fields. It is front-loaded with the primary action and contains no unnecessary words. Every sentence adds value.

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 list tool with one parameter and no output schema, the description adequately states the purpose and return fields. It does not mention pagination or default behavior, but given the simplicity, it is nearly complete. Slightly lacking for full contextual completeness.

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 has 100% coverage with a single optional parameter 'namespace' well-described in the schema. The description adds value by stating the return fields, but does not elaborate on the parameter beyond what the schema provides. Baseline of 3 is appropriate.

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 tool lists metafield definitions for products at the store level, specifying the resource and scope. It differentiates from sibling tools like list_product_metafields (which list values per product) by focusing on definitions. The return fields are listed, adding specificity.

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 implies the tool is for viewing available metafield definitions, but it does not explicitly state when to use it versus alternatives like list_product_metafields or list_customer_metafields. No exclusions or context about when not to use it are provided.

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