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

Annotations declare readOnlyHint=false and destructiveHint=true, yet the description frames the tool purely as a read/search operation ('搜索公开网页信息', '获取搜索结果'), creating an inconsistency with the destructive hint. Beyond that mismatch the description adds no behavioral context such as credit consumption, rate limits, or privacy-mode semantics despite the 'privacy search' mention.

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?

It is a single short sentence with the trigger front-loaded, but it lists overlapping concepts ('隐私搜索结果、网页结果或搜索摘要') that repeat the same idea rather than adding distinct information.

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 9-parameter tool with two enums, no output schema, and a large sibling set of competing search tools, the description leaves critical gaps: it never explains the output-format behavior controlled by 'json', the search_assist/m exclusivity, or how to choose it over sibling search tools.

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 richly documents all 9 parameters (date filter, region, output format, safe search, pagination, caching). The description contributes nothing beyond the schema, 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?

The description states a specific verb+resource: searching public web information via DuckDuckGo and retrieving privacy/web results or search summaries. Naming DuckDuckGo implicitly distinguishes it from siblings like google_search, bing_search, and yandex_search, though it never makes that contrast explicit.

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 whole text is a 'trigger when the user needs...' phrasing but gives no conditions, prerequisites, or when-NOT-to-use guidance. It never tells the agent when to prefer DuckDuckGo over the many other search siblings (google_search, bing_search, yandex_search).

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