check_vnstat_status

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

Annotations already declare readOnlyHint=true, idempotentHint=true, and destructiveHint=false, so the safety profile is covered. The description adds useful detail about what the tool checks (installation, version, interfaces) but does not describe output format or behavior when vnstat is absent. This is consistent with annotations, so no contradiction.

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?

A single, clear, front-loaded sentence conveys the full purpose and output scope with no filler or repetition. Every element earns its place.

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 zero-parameter, read-only status check with no output schema, the description is sufficiently complete: it names all three pieces of information the agent can expect. Annotations cover side-effect safety, and no further prerequisites or return-value details are necessary for correct invocation.

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, so the description does not need to explain argument semantics. Baseline for 0 parameters is 4, and there is no missing parameter-level information.

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 ('Check') and clearly identifies the resource (vnstat) plus the exact information returned: installation status, version, and monitored network interfaces. This distinguishes it from related tools like get_vnstat_data, which would focus on traffic data rather than status.

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 use when you need vnstat installation/version/interface status, but it provides no explicit guidance about when to prefer this tool over alternatives such as check_package_installed or get_vnstat_data. There are no exclusions or conditions stated.

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