List windows

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

No annotations are present, so the description carries the burden of behavioral disclosure. It states it lists windows and names the fields, but does not explicitly state it is read-only or has no side effects. While 'list' strongly implies a non-mutating operation, the absence of any annotation or explicit safety note leaves a small gap. Still, the behavior is clear enough for a simple read tool.

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?

A single, tightly written sentence delivers all essential information: the action, the resource, and the payload fields. No filler words or redundant phrases. The parenthetical enumerating fields is efficient and 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 parameterless listing tool, the description is complete. It tells the agent what the tool does and what data it returns (id, title, key, frame). There is no output schema, so the field list is the only contract, and that is provided. No other contextual details (like ordering, frequency, or limitations) seem necessary for correct invocation.

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 schema coverage is trivially 100%. There is nothing to add about parameter meaning. The description's mention of return fields (id, title, key, frame) gives agents a concrete idea of what to expect, though it doesn't describe how these fields are formatted or whether they correspond to parameter-like filters. Baseline for 0 params is 4.

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 uses a specific verb ('List'), identifies the resource ('the app's on-screen windows'), and enumerates the returned fields (id, title, key, frame). It clearly distinguishes from siblings like get_ui_tree (UI hierarchy) and screenshot (image capture), making the tool's purpose 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 provides no guidance on when to use this tool versus alternatives. For example, it doesn't state that this should be used to enumerate open windows before interacting with them, nor does it mention any exclusions (e.g., 'use get_ui_tree for widget-level details'). An agent is left to infer usage context from the tool name and sibling list.

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