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

Annotations already declare a non-destructive, idempotent mutation (readOnlyHint=false, idempotentHint=true, destructiveHint=false), so the description needn't restate that. It adds genuinely useful context beyond the annotations, namely the 【需要登录】 authentication requirement, though it says nothing about permission scope or side effects.

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 compact sentences with the auth constraint front-loaded and the example appended; there is little wasted text. The parenthetical and bracketed example are helpful but slightly heavy for what could be a single sentence, keeping it just short of a 5.

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 three-parameter mutation with annotations covering the safety profile and no output schema, the description supplies the needed context: purpose, match key, allowed values, and auth requirement. It lacks only details on permissions or post-change effects, a minor omission.

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 the baseline is 3. The description meaningfully adds to it by explaining that links are matched by url and that type optionally narrows the match, plus enumerating the allowed visibility values — going beyond the bare schema field descriptions.

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 names a specific verb (把...可见范围改成) and a specific resource (当前用户某条链接), plus the exact target values (public/friends/private). It clearly distinguishes itself from sibling link tools like add_profile_link and remove_profile_link, so an agent can identify it without opening the schema.

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 states the login requirement upfront and explains the match key (url, optionally narrowed by type), which tells the agent when this tool applies. It offers a concrete example but does not name alternatives or explicit when-not conditions, so it falls short of a 5.

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