disk_usage

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

With no annotations provided, the description carries the full burden of behavioral disclosure, but it only states the basic action. It doesn't mention whether it scans recursively, requires permissions, how errors are handled, or what the output includes, leaving the agent without crucial 'beyond the name' information.

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 sentence with no wasted words, achieving good conciseness and front-loading. However, it is so minimal that it lacks structure and supplementary detail that could be present without sacrificing conciseness, so it doesn't earn a 5.

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?

Despite the tool's simplicity with one optional parameter, the lack of an output schema and annotations means the description must explain what 'disk usage information' actually includes (e.g., total, free, used). It doesn't, leaving an agent uncertain about the response format and tool's full capabilities.

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?

Schema description coverage is 100% with the 'path' parameter described as 'Path to check (default: /)'. The description adds no additional meaning beyond the schema, but the schema is sufficient, so the baseline of 3 is appropriate.

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 with 'Get disk usage information', which is a specific action on a resource and distinguishes it from sibling tools like system_info or system_exec. However, it is somewhat generic and doesn't specify the scope or format beyond the name, so it's not a full 5.

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 provides no guidance on when to use this tool compared to alternatives, nor does it mention prerequisites or exclusions. It simply states the action with no context, so an agent has no basis for choosing this over siblings like system_info.

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