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

The description goes well beyond the annotations by disclosing login requirements, soft-delete semantics, idempotency behavior, the fact that the full preference list is returned, and the non-obvious silent eviction of the oldest entry at the cap. These behavioral details add significant context that annotations alone do not provide.

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 organized into two dense sections: the first covers the core effect, idempotency, and return value; the second covers the usage chain and quota warning. Every sentence earns its place, and the most important information is front-loaded.

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 single-id mutation with no output schema, the description is self-sufficient: it explains what happens, what is returned, where the id comes from, that login is required, that the operation is idempotent, and the quota-related edge case. An agent has enough information to invoke it 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?

There is only one parameter, id, and the schema already describes it as the preference id obtained from list_my_match_preferences, so schema coverage is 100%. The description repeats this chain but does not add format, constraint, or edge-case meaning beyond the schema baseline.

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 and resource ('撤掉一条破冰匹配偏好') and clarifies the operation semantics by saying the row is set to REVOKED rather than deleted. It is clearly distinguishable from sibling tools like list_my_match_preferences and set_my_match_preference.

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 explicitly gives the intended chain: use list_my_match_preferences to get the id, then call this tool, and provides concrete guidance for the 20-item cap by recommending revocation of needOpen=false entries first. It does not explicitly name a when-not-to-use alternative such as set_my_match_preference for re-adding, so it stops short of a full 5.

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