Set listing quantity

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

With no annotations provided, the description carries the full burden of behavioral disclosure. It only states the action ('Sets the fulfillment quantity') but does not mention side effects, such as whether this triggers a feed submission, whether it is reversible, or what the response looks like. It also does not explain the significance of the 'DEFAULT channel' beyond a qualifier. This is insufficient for a mutation tool with zero annotation coverage.

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 a single, tight sentence that states the action and a key scoping qualifier. There is no fluff or repetition. It is optimally concise and front-loaded.

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 mutation tool with three required parameters and no output schema or annotations, the description is under-specified. It omits any mention of return values, error conditions, prerequisites (e.g., product type must be valid), or the operational impact (e.g., feed submission). An agent would need to infer too much about the tool's 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?

Schema description coverage is 100%, so the schema already documents all three parameters (sku, quantity, productType) including the meaning of quantity (0 to remove the buyable offer). The description adds only the channel context, not parameter-specific meaning, so it does not go beyond the schema. Baseline 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 verb 'Sets' and the resource 'fulfillment quantity for a SKU', with an explicit channel qualifier '(merchant-fulfilled / DEFAULT channel)'. It is specific and unambiguous, but it does not reference any sibling tool to differentiate, so it does not fully earn a 5.

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 channel qualifier implies that this tool is for merchant-fulfilled listings only, which provides some usage context. However, it does not explicitly state when to use this tool versus alternatives (e.g., for FBA or other channels), nor does it mention any prerequisites or exclusions.

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