niri_set_column_width

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

No annotations are provided, so the description must carry the full burden. It does list valid width options, which is useful behavioral information, but it does not disclose side effects, error handling, or whether the operation is reversible. This is a minimal viable disclosure, hence a 3.

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 extremely concise: a single statement plus a list of options. No fluff, every word earns its place, and the main verb is front-loaded.

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 one-parameter tool, the description covers purpose and parameter values, and an output schema exists for return values. However, it lacks usage context and behavioral details (e.g., side effects, error behavior), which is a noticeable gap given the absence of annotations. It is adequate but not thorough.

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 schema provides no description for the width parameter (0% coverage), but the description compensates by enumerating all valid values: '50%', '33.333%', '+10%', '-10%', 'switch-preset', or 'expand'. This adds significant meaning beyond the bare string type, though it does not explain the semantics of each option.

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+resource: 'Set focused column width.' This clearly distinguishes it from sibling tools like niri_focus_window or niri_move_window_direction. The listed width options further clarify the exact purpose.

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?

Usage is implied by the tool's specificity—it is clearly for adjusting the focused column's width—but no explicit guidance on when to use it versus alternatives is given. No exclusions or prerequisites are mentioned, so it is not a clear 4 or 5.

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