List CDN resources

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

Even with readOnlyHint and openWorldHint annotations, the description adds critical behavior: the API paginates with an undocumented default of 25, the tool requests up to 100 per call, and the agent MUST check meta.total and fetch remaining pages before reporting. This transparently disclosers a non-obvious pitfall and gives explicit instruction on how the tool behaves.

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 three sentences, each earning its place: purpose, pagination nuanced behavior, hard instruction to paginate. It is front-loaded with the most important information and contains no filler.

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?

Given a 3-parameter tool with no output schema, the description provides sufficient context by naming exactly what is returned (settings, domains, state), explaining pagination, and warning about the meta.total pitfall. The input schema documents the parameters and additionalProperties false, and the annotations add the open-world/read-only context. Together this is a complete picture for an agent to use the tool effectively.

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 covers 100% with descriptions for page, per_page, and traffic_distribution, so the bar for adding value is partly satisfied. The description goes beyond the schema by explaining why pagination parameters matter ('API paginates, its own default is 25 per page, undocumented') and why the agent needs to use page, effectively clarifying the purpose behind page/per_page behavior.

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 opens with a specific verb and resource: 'List Anycast CDN resources (pull zones) in the account with their settings, domains and state.' It clearly distinguishes this as the account-level listing tool, contrasting with siblings like get_cdn_resource and get_cdn_metrics by focusing on the enumeration of CDN resources themselves.

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: this is for listing all Anycast CDN resources in the account, and it instructs the agent to paginate through meta.total until all resources are retrieved. However, it does not explicitly call out when to prefer get_cdn_resource for a single zone or mention any exclusions, so it falls short of full explicit alternative guidance.

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