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

Annotations already establish readOnly and openWorld, and the description adds genuinely useful behavior: PA-API products when the default storefront is configured, otherwise Mother's Day deep-link cards plus catalogMatches. That dual-mode return path is exactly the kind of context annotations cannot express, though rate limits and result-count behavior are unmentioned.

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?

Three tight sentences, front-loaded with purpose then behavior then the mandatory-parameter rule. The trailing 'OpenAPI: searchAmazon' is a low-value pointer but costs little.

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 an 8-parameter tool with no output schema, the description does the important work of explaining what comes back in each mode. The gap is the filter parameters (budgetBand, occasion, interest) whose semantics are left entirely to enum values.

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 63%, so the schema already documents q, locale, styleTag, and marketplace. The description reinforces marketplace/locale as mandatory and 'for the end user', which adds a real directive, but says nothing about limit, budgetBand, occasion, or the interest/styleTag alias.

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?

States a specific verb and resource — searching Amazon for Mother's Day gift ideas on the user's marketplace — plus a fallback behavior. It is clear on its own, but never names or contrasts with the obvious sibling suggest_gifts, so sibling differentiation is left to inference.

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?

'ALWAYS pass marketplace + locale for the end user' is a parameter directive, not guidance on when to pick this over suggest_gifts or get_catalog. The condition that changes behavior (default storefront configured vs not) is described as an output consequence rather than a reason to choose the tool.

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