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

Annotations already flag destructive, idempotent, and non-read-only behavior. The description adds meaningful context beyond those flags: login is required, and the operation returns ok even if the user was not blocked. No contradiction with annotations.

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 concise sentences with no filler. The login requirement is front-loaded, and the idempotency behavior is stated efficiently.

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 one-parameter tool with no output schema, the description covers auth requirements, the core action, idempotency, and the return value. It could be slightly more complete by explicitly naming block_user as the counterpart or addressing invalid-user behavior, but the low complexity makes this nearly complete.

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 already documents userId as '要取消拉黑的用户 id'. The description does not add anything new about the parameter beyond what the schema 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 states a specific action ('取消对某用户的拉黑' - unblock a user) with a clear target resource. This unambiguously distinguishes it from block_user and other user-related mutation 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 usage context is implied: use this tool to undo a block on a user, especially as the counterpart to block_user. However, the description does not explicitly name alternatives or state when not to use it.

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