get_system_hostname

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

Annotations indicate readOnlyHint=true and destructiveHint=false, which already convey the safe, read-only nature. The description adds no further behavioral details (e.g., authentication requirements or side effects), but none are needed for such a simple getter. It does not contradict 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 a single, front-loaded sentence with no redundant words. It effectively communicates the tool's purpose in minimal space, earning the highest score for conciseness.

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?

Given the tool's simplicity—zero parameters, a read-only annotation, and an output schema that presumably defines return values—the description is complete. No additional context is required for an agent to invoke this tool correctly.

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 input schema is fully covered. As per the rubric, a baseline of 4 is given for 0-parameter tools; the description provides no parameter-specific details because there are none to describe.

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 'Get the current system hostname and domain' uses a specific verb ('Get') and resource ('hostname and domain'), clearly distinguishing it from sibling tools like get_system_version or get_system_timezone. It precisely states what the tool does without ambiguity.

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 context is clear: use this tool when you need the system's hostname and domain. No exclusions or alternatives are mentioned, but given the trivial nature of a parameterless getter, the intended usage is self-evident. It doesn't explicitly compare to alternatives, but none are directly applicable.

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