Focus a window

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

No annotations are provided, so the description carries full responsibility for behavioral disclosure. It only states the action without mentioning side effects, idempotency, whether focus movement is relative, or any failure conditions. It does not contradict annotations (none exist), but it adds no extra behavioral context beyond the action itself.

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, efficient sentence with zero filler. It front-loads the core action and direction, making it immediately scannable. No unnecessary details are included, and it is appropriately sized for a one-parameter tool.

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 tool with one enum parameter and no output schema, the description covers the essential purpose and action. It does not explicitly explain that 'neighboring' is relative to the current focus, but that is implied by the term. Given the low complexity and absence of annotations, the description is sufficiently complete, though it could briefly note that it operates on the currently focused window.

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 input schema has 100% coverage with a clear enum description ('l=left r=right u=up d=down'). The description does not add any meaning beyond the schema, so the baseline of 3 applies. Since the schema fully documents the single parameter, this 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 states a specific verb ('Move focus') and resource ('neighboring window') with a directional qualifier. It clearly differentiates from sibling tools like window_close or window_swap by specifying the focus action. The title reinforces this, and the phrase 'neighboring window' implies relative to the currently focused window, which is unambiguous.

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 usage context (navigating focus between windows) but provides no explicit guidance on when to use this tool versus alternatives like window_swap or window_snap. There are no exclusions or conditions stated, so an agent must infer applicability from its own reasoning.

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