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

Annotations declare readOnlyHint=false, destructiveHint=true and openWorldHint=true, and the description adds no behavioral context at all — nothing about cost/credits, caching (only the no_cache parameter documents that), rate limits, or pagination behaviour. With a destructive annotation on a query tool, the agent would benefit from clarification, and the description supplies none.

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?

A single, front-loaded sentence with no filler or repetition. The long enumeration of features is slightly list-heavy but each item corresponds to a real capability, so nothing feels wasted.

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 16-parameter tool with no output schema and a destructive annotation, the description covers only trigger conditions. The schema compensates fully for parameter meaning, but return-format expectations, caching/cost implications and pagination are left to the schema or undocumented, leaving meaningful gaps.

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% and the schema itself documents every parameter in detail, including cross-parameter rules (shoprs vs q, overrides of shoprs filters, uule vs location). The description adds no parameter meaning beyond that, so the 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?

Names a specific resource (Google Shopping 商品搜索结果) and enumerates the abilities: prices, promotions, free shipping, small-business items, price ranges and filters. That is clear enough to identify the tool, but it never contrasts itself with near siblings such as google_shopping_info or bing_shopping, so an agent has no textual basis for choosing between them.

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 sentence is written entirely as a trigger condition, listing concrete situations in which to call it (price lookup, promotions, free shipping, small business, price-range/sort/filter retrieval). This is solid when-to-use guidance, but there are no exclusions or named alternatives when another shopping/search sibling would fit better.

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