VPS statistics

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

Annotations already declare readOnlyHint, openWorldHint, idempotentHint, and destructiveHint, covering the safety profile. The description adds semantic context for the kind parameter (processor load vs network transfer) but does not disclose behavior such as return format, time range, or aggregation. Given the strong annotation coverage, this is acceptable 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 two sentences, front-loaded with the core purpose and immediately followed by the parameter explanation. Every word earns its place, with no redundant information or padding.

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 stats tool with three parameters and clear annotations, the description is adequate but does not explain the output format (e.g., time series vs. aggregate). With no output schema, some guidance on the return structure would be beneficial. However, the tool's simplicity and the siblings' patterns partially compensate. A short note on what the statistics look like would make it more 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 schema covers all parameters with descriptions (100% coverage), but the description adds meaning beyond the schema by clarifying that kind selects the series and providing concrete meanings for 'cpu' (processor load) and 'traffic' (network transfer). This helps the agent understand the enum values more intuitively. The vpsId and userId parameters are adequately described in the schema and don't need additional explanation.

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 tool's function: it returns usage statistics for a VPS, and specifies the two series (cpu and traffic) via the kind parameter. This distinguishes it from other stats tools like ws_hosting_stats or ws_db_stats by the resource type, and from ws_vps_get which retrieves VPS details rather than statistics.

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 usage for VPS statistics, but does not explicitly state when to use it over alternatives or provide exclusions. It doesn't mention that other stats tools exist for other resources, though the resource specificity makes the intended use clear. No direct guidance on selecting this tool vs. siblings.

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