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

With readOnlyHint=true and openWorldHint=true annotations, the safety profile is already covered. The description adds meaningful context by clarifying that only public posts are returned and that page_token pagination is supported, going slightly beyond what the annotations state.

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 entire description is one compact, front-loaded sentence that covers the core purpose, usage condition, and pagination support. Every clause adds value with no redundancy.

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 two-parameter tool with 100% schema coverage, a true output schema, and safety annotations, the description sufficiently covers purpose, usage condition, and pagination. Nothing essential is missing for an agent to call this tool correctly.

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%, with detailed explanations for both user_id and page_token. The description itself adds little beyond reinforcing that user_id should be complete and passed directly, so the baseline of 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 and resource ('根据 X 用户 ID 获取公开用户帖子列表' - get public user posts by X user ID), and explicitly notes it should be used when a complete user_id is already available. This clearly distinguishes it from the by_username and by_profile_url sibling tools.

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 description gives clear context for when to use the tool: when a complete user_id is already available, use it directly. However, it does not explicitly mention when not to use it or name the alternative by_username/by_profile_url tools, though sibling names make the distinction evident.

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