Get vCDN files totals

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

Annotations already declare readOnlyHint=true and openWorldHint=true, covering the read-only safety profile. The description adds that the tool returns total count and size, which is slightly more specific than the title, but it does not disclose additional behavior such as whether the totals are aggregated globally, response format, or performance implications. With annotations present, 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, concise sentence: 'Get total count and size of files stored on the Video CDN.' It contains no fluff or repetition, and every word contributes meaning. It is front-loaded with the verb and object, making it instantly scannable.

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 that there are no parameters, no output schema, and annotations already indicate read-only/open-world behavior, the description is sufficient to understand the tool's core function. It clearly states the tool returns total count and size for files on the Video CDN. However, it could explicitly mention that it returns a single aggregated result (rather than a list), though this is reasonable inferred from 'total'. The absence of advanced features keeps the description complete.

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 has zero parameters, and the schema description coverage is 100% (empty properties). The baseline for 0 params is 4, and the description does not need to explain parameters. The description 'Get total count and size' already indicates the return value matches the tool's purpose, so no further param semantics are needed.

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 clearly states the verb ('get') and resource ('total count and size of files stored on the Video CDN'). It is specific enough to distinguish from siblings like list_vcdn_files (which likely lists individual files) and get_vcdn_statistics (which may cover broader metrics). The scope is 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 implies when to use this tool (when you need aggregate file totals), but it does not explicitly mention alternatives or exclusions. Sibling tools like list_vcdn_files suggest different use cases, but the description itself does not guide the agent to choose this over other tools. No direct when/when-not guidance is provided.

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