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

Annotations already declare readOnly/openWorld/non-destructive, so the safety profile is covered. The description adds real behavioral context beyond that: pagination semantics, location/zip scoping, the `noResults` flag, and the `searchInformation` echo block. It omits rate limits, auth requirements, and result-count caps per page.

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?

Front-loaded with the core action, then the return shape, then use cases — a sensible order. The return-field enumeration is long but earns its place given there is no output schema; a few items (Prime/sponsored flags, position) could be trimmed without loss.

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?

With no output schema, the description carries the full burden of describing returns, and it does so thoroughly — per-result fields plus the searchInformation block and noResults flag. Combined with the 100%-covered input schema, an agent has everything needed to call and interpret this tool.

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 baseline is 3, but the description adds meaning by spelling out the sort orders in human terms (featured, price low-to-high, avg-customer-review, newest) and by framing deliveryZip/shippingLocation as location scoping. It does not clarify the interaction between language and domain beyond noting the dependency.

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 ('Runs a keyword search on a chosen Amazon domain') and enumerates the scoping controls (pagination, delivery zip, sort order). It also distinguishes itself from siblings by naming the downstream product/reviews endpoints that consume the harvested ASINs.

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?

Provides concrete use cases (SERP monitoring, share-of-shelf tracking, competitor discovery, ASIN harvesting, price-comparison agents) that tell an agent when this tool is the right entry point. It stops short of explicit when-not conditions or a direct 'use X instead' routing statement.

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