nacos_list_instances

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

No annotations are provided, so the description carries the full behavioral burden. '查询' implies a read-only lookup, and the health-filter behavior is disclosed, but there is no mention of pagination, result ordering, default group/namespace behavior, or what the returned instance records contain. Adequate for a simple read, but thin given zero annotation coverage and no output schema.

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 front-loaded sentence with no filler; the core action comes first and the filtering capability follows. It is efficient, though its brevity reflects under-specification of behavior rather than tight editing, keeping it just below 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?

With five well-documented parameters but no output schema, the description should ideally sketch what an instance list returns (instance IDs, IPs, health flags, cluster layout). It omits this, leaving the agent to infer the response shape. The essentials for calling the tool are present, so it is minimally complete rather than rich.

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 all five parameters (clusters, groupName, healthyOnly, namespaceId, serviceName) are already documented in the schema, including defaults. The description's mention of health filtering merely restates the healthyOnly parameter already covered, adding no syntax or format detail beyond the schema. Baseline 3 applies.

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?

States a specific verb and resource (查询...实例列表) scoped to instances registered under a microservice, which clearly separates it from siblings like nacos_list_services or nacos_get_service. It also names the filtering capability (按健康状态过滤). It does not explicitly name a sibling to contrast with, so it stops short of a 5.

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 when-to-use guidance, no prerequisites, and no alternatives named — nothing tells the agent why to pick this over nacos_list_services or nacos_get_service. The only usage hint is the implied ability to filter by health status, which is really a parameter capability rather than routing guidance.

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