arch_brightness_control

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

With no annotations provided, the description carries the full burden of disclosing behavioral traits. It states the action can be 'get' or 'set', which implies a read vs. mutate distinction, but it does not disclose side effects, permission requirements, failure modes, or what the tool returns. This is insufficient for a tool that can alter system state via brightnessctl.

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 very concise, with a single opening sentence and two short parameter lines. It front-loads the core purpose and contains zero filler. Every sentence adds value, making it highly efficient.

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?

The tool is simple (2 optional params, output schema exists) but the description still misses important context: prerequisites (does brightnessctl need to be installed?), error conditions, and more explicit parameter relationships (e.g., percent ignored when action=get). The output schema covers return values, but the description could be more thorough for a mutation-capable tool.

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 0%, so the description must compensate. It provides explicit meanings for both parameters: 'action: get or set' and 'percent: Target brightness percentage integer (1-100) when action is set', which goes beyond the bare schema. However, it could be clearer about whether percent is required for 'set', or what happens if percent is omitted or invalid, so not a perfect score.

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 'Query or adjust screen brightness using brightnessctl', with a specific verb ('Query or adjust'), resource ('screen brightness'), and mechanism ('brightnessctl'). This distinguishes it from sibling tools like arch_audio_control, fulfilling the purpose clarity requirement.

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 when to use the tool (for brightness operations) via its primary purpose line, and the param explanations give some usage guidance (e.g., 'action: get or set'). However, it does not explicitly state when to use this tool versus alternatives (e.g., arch_audio_control for audio), or provide any exclusion conditions, so it falls short of a higher score.

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