cdn_get_cdn_zone_stats

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

With no annotations, the description carries the burden of explaining behavior. It discloses 'smart identifier resolution' and the returned metrics, which is useful context. However, it does not explicitly state that this is a read-only operation, nor does it mention auth requirements or potential errors. The behavior is implied by 'Get statistics' but not fully disclosed.

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 compact and well-organized, with a one-line summary followed by labeled Args and Returns sections. There is minor redundancy between the opening sentence and the Returns line, but overall every sentence adds value and the essential information is front-loaded.

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 one-parameter get-stats tool, the description covers the critical aspects: what the tool does, how to identify the zone, and what the response includes. The presence of an output schema further supports the return-value expectations. Missing details like error handling, permissions, or metric time ranges are minor given the tool's simplicity.

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 provides only a generic string property, making the description essential. The Args section clarifies that zone_identifier accepts an origin domain, CDN domain, or ID, adding significant meaning beyond the schema. This compensates well for the 0% schema description coverage.

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: 'Get statistics for a CDN zone'. It also lists the returned metrics (bandwidth, requests, cache hit ratio), which distinguishes it from related CDN tools like cdn_get_cdn_zone or cdn_get_cdn_zone_logs. However, it does not explicitly differentiate from cdn_get_cdn_zone_summary, which may overlap in purpose.

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 explains how to specify the zone (origin domain, CDN domain, or ID) but gives no guidance on when to choose this tool over cdn_get_cdn_zone_summary, cdn_get_cdn_zone_logs, or cdn_analyze_cdn_performance. No alternative tools are named and no context is provided for when this stats retrieval is preferable.

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