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

The description adds no behavioral context beyond the readOnlyHint annotation. It simply says 'get' which aligns with the annotation, but doesn't disclose any additional traits such as potential null returns, required auth, or differences from the profile_url variant. With annotations already covering the safety profile, the description fails to add extra transparency.

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 a single short sentence that is direct and front-loaded. Every word serves a purpose, with no redundancy or filler.

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 one parameter, an output schema, and annotations, the description is nearly sufficient. It lacks explicit differentiation from the sibling profile_url tool, but this is a minor gap given the self-explanatory name and other structured context.

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 description covers the only parameter fully (user_id with reuse guidance), so the tool description doesn't need to add more. Baseline of 3 is appropriate because the description itself doesn't enhance parameter understanding beyond what the schema already provides.

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 '根据 user_id 获取微博用户资料' clearly states the tool's function: getting a Weibo user profile by user_id. It uses a specific verb and resource and distinguishes itself from the sibling tool weibo_get_user_info_by_profile_url by explicitly mentioning user_id.

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 implies usage when user_id is available, but it does not explicitly state when to use this tool over the profile_url variant or mention any exclusions. The schema description provides a hint about reusing user_id, but there is no explicit 'use this when...' guidance.

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