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

Annotations already declare readOnlyHint and openWorldHint, so safety is covered. The description goes further with operational context an agent needs: page-based pagination and, notably, that Baidu occasionally challenges requests with a 503 that should be retried. This is real behavioral value beyond structured fields.

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 tight sentences: the first covers output shape and pagination, the second covers usage scope and the retry caveat. Front-loaded with the core action and no wasted phrasing.

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?

An output schema exists, so the description's enumeration of return fields is helpful redundancy rather than a requirement. Query semantics, pagination, and the retry behavior are all covered; only the absence of explicit alternative-tool routing keeps it from a 5.

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%, so both q and page are already documented in the schema, including the Chinese-query hint and the 1-10 page bound. The description adds only the generic notion of pagination, so 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 (Searches) and resource (Baidu's mobile web results) and even enumerates the return card fields. The Baidu-specific scope clearly distinguishes it from the many other *_search siblings such as bing_search or google_news_search.

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?

Explicitly states the use case ('Use for Chinese-language web research'), which is genuinely differentiating guidance. However it names no alternative tool for non-Chinese research and gives no when-not condition beyond the implicit language scope.

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