listSubscriptions

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

The readOnlyHint and openWorldHint annotations already establish safety and closed-world behavior, so the description only needs to add operational context. It adds that the tool reports active subscription state and buffered message count, but it does not describe the response shape or any additional behavioral quirks. 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?

One short sentence conveys the action, scope, output fields, and intended use with no redundant wording. The core listing behavior is front-loaded before the debugging/monitoring note.

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 parameterless read-only monitoring tool, the description covers what it lists, the fields returned, and why it would be used. The lack of an output schema means the exact response format is not specified, but the described status and buffered message count provide enough orientation for an agent to call and interpret the tool.

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 input schema has zero parameters and 100% schema description coverage, so there is no parameter semantics burden for the description to carry. According to the zero-parameter baseline, this dimension is well satisfied.

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?

Description uses a specific verb ('列出'/'list') and clear resource ('当前所有活跃订阅'/'all current active subscriptions') and names the returned fields (status, buffered message count). It is unmistakably distinct from sibling subscription tools such as startSubscription, stopSubscription, and the many subscribe* operations.

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?

States its intended use context ('用于调试和监控' / for debugging and monitoring), implying it is a read-only inspection tool rather than a tool that starts or stops subscriptions. It does not explicitly compare against alternatives or state when not to use it, but the intended context is clear.

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