Check stock

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

With no annotations, the description carries the full behavioral burden. It discloses the return values (found, in stock, remaining quantity when a low-stock threshold is exposed), but does not explicitly state that it is a read-only operation, nor does it cover error handling, permissions, or rate limits. Some behavioral traits remain unspecified.

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 sentences with no wasted words. It front-loads the action and expected output, then gives a practical usage note. Every sentence contributes 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 one-parameter tool with no output schema, the description adequately covers what the tool does, what it returns, and when to use it. It is missing details like error handling and authorization, but the tool is straightforward enough that these are not critical for correct 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?

Schema coverage is 100%, so the skus parameter is fully documented in the schema. The description's mention of 'by SKU' and 'one or more products' reinforces the parameter's purpose but adds minimal new meaning beyond the schema. Baseline 3 applies.

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 identifies the tool as a stock-availability check by SKU and specifies the per-SKU return fields. It is specific enough to distinguish from sibling tools like get_product or search_products, but it does not explicitly name alternatives, so it falls short of 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 description gives an explicit usage directive: 'Use this to confirm availability before recommending or ordering items.' This provides clear context for when to call the tool, though it does not mention when not to use it or reference alternative tools, preventing a 5.

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