get_disk_usage

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

No annotations are provided, so the description carries the full burden. It explicitly discloses a key behavioral trait: 'Does not modify system state' (a read-only guarantee). It also clarifies scope ('all mounted partitions'). For a simple zero-parameter monitoring tool, this is sufficient and helpful.

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 with zero filler. The first sentence front-loads exactly what the tool returns; the second gives usage guidance and a safety note. Every word 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-argument, read-only system monitoring tool with an output schema, the description covers purpose, output specificity, usage context, and safety. Nothing an agent needs to decide whether or how to call it is missing. The output schema likely details the return structure, so the description does not need to repeat it.

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 baseline is 4. There is no parameter information to add, and the description naturally does not attempt to explain nonexistent parameters. The output schema is not shown but its existence covers return fields.

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 states a specific verb ('Returns') and resource ('disk usage for all mounted partitions') and spells out the output fields (total, used, free in GB, used percentage per mount point). It is clearly distinct from sibling monitoring tools like get_cpu_usage or get_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 description provides explicit when-to-use context: 'when investigating low disk space, full partitions, or storage issues.' It does not name alternatives or when-not-to-use, but the tool's specificity makes that unnecessary. The added note 'Does not modify system state' further guides safe usage.

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