disk_usage

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

Annotations already declare readOnlyHint=true, idempotentHint=true, and destructiveHint=false. The description adds value beyond this by specifying the exact output breakdown (size / used / free / percentage) and the df -h equivalence, giving a clear behavioral model without contradicting the annotations.

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 concise and well-structured: a one-line purpose with a familiar command equivalence, followed by compact Args and Returns sections. Every sentence carries useful information and there is no redundant text.

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 read-only monitoring tool, the description plus annotations and schema cover the essential information: what it returns, the parameter meanings, and the non-destructive/idempotent nature. It could be more complete with explicit alternatives or error conditions, but nothing critical is missing for basic 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 description merely lists 'host, response_format' without adding semantic detail beyond the input schema. However, the schema's nested HostOnlyInput definition already documents both parameters well, including host default behavior and response_format meaning, so no critical parameter information is missing.

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 identifies the resource as 'csatolt fájlrendszerek kihasználtsága' (mounted filesystem usage) and anchors it with the well-known 'df -h ekvivalens' equivalence. This immediately distinguishes it from sibling tools like cpu_usage and memory_usage.

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 'df -h equivalent' statement gives implied context for when to call the tool, but there is no explicit when-to-use guidance, exclusion criteria, or mention of an alternative tool. An agent can infer usage, but the description does not actively route between alternatives.

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