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

Beyond the readOnlyHint and openWorldHint annotations, the description adds useful behavior: data is real-time, cached for 5 minutes, free, and requires no API key. It does not mention rate limits or response-shape details, but the annotations already cover the safety profile.

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?

The description is front-loaded and contains no filler, but the English and Chinese versions repeat the same information, roughly doubling length. The repetition is intentional for bilingual clarity but is still redundant.

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 simple read-only tool with two optional parameters, no output schema, and complete schema descriptions, the definition covers data source, freshness, cost, authentication, and caching. Nothing essential for correct invocation is missing.

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?

The schema already documents both parameters at 100% coverage, including platform values, 'all', limit range, and default. The description reinforces platform coverage but adds no syntax or semantics beyond the schema, so the baseline 3 is appropriate.

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: live trending/hot lists from named Chinese platforms, with the full platform scope including 'all'. It is immediately clear what the tool returns and for which sources.

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?

It gives clear usage context: real-time hot lists, cached for 5 minutes, free, and no API key required. It does not explicitly say when not to use it, but the sibling tools are unrelated, so the intended use is unambiguous.

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