ncloud_globalcdn_list_instances

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

Annotations declare readOnlyHint=true, and the description aligns with a read-only listing operation. The description adds the optional filtering and pagination behavior, but does not disclose additional details like return format or default pagination size. Given annotations cover safety, this is adequate but not rich.

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 a single, front-loaded sentence with no filler. Every word contributes meaning, efficiently conveying the action, resource, and optional parameters.

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 list tool with optional filters and read-only annotations, the description is sufficiently complete. It does not specify return format, but the tool name and schema provide adequate context for an agent to select and 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?

The schema already provides 100% coverage for all three parameters. The description paraphrases them as 'filtering by instance number and pagination', which adds a high-level grouping but no new syntax or constraints beyond the schema.

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 uses a specific verb ('List') and resource ('Global CDN instances'), clearly distinguishing it from sibling tools like ncloud_cdnplus_list_instances. It also mentions the optional filtering capability, making the purpose unambiguous.

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?

The description provides clear context for when to use this tool: listing Global CDN instances, with optional filtering and pagination. It does not explicitly exclude alternatives, but the resource scope ('Global CDN') inherently differentiates it from other list tools in the sibling set.

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