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

With no annotations, the description carries the burden of behavioral disclosure. It mentions what information is shown (in-stock/out-of-stock, prices, delivery info, sellers) but does not clarify read-only nature, data sources beyond platform names, or behavior when no match is found. The description adds some context but leaves gaps in behavior.

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 a clear, front-loaded verb and resource. Every word contributes to understanding the tool's purpose and outputs, with no filler or redundancy.

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?

The description provides a general outline of returned data (stock status, prices, etc.) but lacks details on parameter combinations, the necessity of at least one identifier, or edge cases. Without an output schema, it should clarify more about invocation constraints, making it partially complete.

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 documents all three parameters with descriptions (100% coverage), so the baseline is 3. The description does not add additional meaning about parameter usage, such as whether 'asin' and 'query' are mutually exclusive or if at least one is required. No extra value is provided beyond the schema.

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 'check' targeting 'product availability and stock status' across Amazon and Google Shopping. This distinguishes it from price-focused siblings like compare_prices and product_search, making the tool's purpose specific and unambiguous.

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 checking availability and stock, which suggests when to use it, but it does not explicitly state alternatives or exclusions. No mention of when to prefer compare_prices or product_search is provided, leaving usage guidance implicit rather than explicit.

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