List Custom Isp Rules

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

With readOnlyHint=true already declaring the safe-read profile, the description adds no behavioral context of its own — no mention of scope, filtering, ordering, or pagination. For a no-argument list tool this is tolerable, but the description contributes nothing beyond the annotation.

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?

A single short phrase, front-loaded with the verb and resource, with no wasted words. It is concise to the point of terseness rather than padded.

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?

An output schema exists and there are no parameters, so return-value detail and input semantics are already covered by structured fields. What remains missing is scope context — whether the list is filtered, complete, or ordered — which for a simple read tool is a minor but real gap.

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 tool takes zero parameters, so there is nothing for the description to clarify; the baseline for a parameterless tool is 4. No parameter claims are made that could mislead.

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 (列列出) and resource (自定义运营商规则 / custom ISP rules), so an agent knows it returns a list of custom carrier rules. However, it offers no differentiation from the many other list_* siblings (list_custom_protocols, list_hosted custom libraries, list_load_balance_rules, etc.), so the agent must rely on the name alone to disambiguate.

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?

There is no guidance on when to call this versus any alternative, nor any prerequisite or scope note. The phrase simply states the action; usage must be inferred entirely from the tool name.

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