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

Annotations already declare readOnly, idempotent, non-destructive, open-world behavior, so the safety profile is covered. The description still earns credit for adding two decision-relevant facts the annotations do not carry: pagination behavior ('across paginated results') and billing cost ('1 point per returned record'), which directly affects how an agent sizes max_items.

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?

Two sentences, no filler, and the core action plus output shape is front-loaded before the cost note. Every clause carries information the agent needs.

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 usefully names the returned fields and discloses pagination and per-record cost. What is missing is any hint of how start_page/max_items interact with paging or where results are truncated, but for a four-parameter search tool this is close to sufficient.

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%, including a fully enumerated domain list and defaults for max_items, start_page, and domain, so the schema does the heavy lifting. The description adds nothing beyond implying pagination and cost-per-record; 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?

States a specific verb (search/extract) and resource (Amazon product listings) and even enumerates the returned fields (title, URL, price, rating). It is clear on its own, but it never names the obvious alternative run_amazon_product (single-product lookup) or run_amazon_seller_products, so the agent must infer the distinction from names alone.

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?

There is no when-to-use guidance, no prerequisites, and no routing to alternatives despite four Amazon siblings and dozens of other marketplace search tools. The agent can infer that a search tool is for discovery, but nothing in the text helps it choose between this and run_amazon_product_search equivalents on other domains.

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