List what is on the desktop

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

Annotations already declare readOnlyHint=true, so the safety profile is covered, and the description adds an environment constraint not present anywhere else: 'Linux only.' It still omits return-volume or pagination behavior, but the platform caveat is a genuinely useful behavioral disclosure beyond the structured fields.

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?

Front-loads the resource and its fields, then compresses usage guidance and the class-vs-title rule into two tight sentences. The 'browser that failed to open' clause is slightly literary but earns its place as usage guidance; every sentence carries signal.

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?

With no output schema, the description compensates by naming the returned fields, and the Linux-only note plus class/title guidance cover the main correctness pitfalls. For a simple two-parameter read tool this is nearly complete; only window ordering/count behavior is unaddressed.

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 100%, so both computer_id and include_all are already documented, including the 'panels, wallpaper and other furniture' rationale. The description adds no parameter-level syntax or defaults beyond that, so the baseline 3 applies.

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?

States a specific resource (windows known to the window manager) and enumerates the returned fields (id, title, class, geometry, focus). It actively distinguishes itself from the sibling screenshot tool ('A screenshot says what the desktop looks like; this says what any of it is'), so an agent can route correctly without opening either schema.

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?

Gives a concrete decision context versus screenshot (diagnosing a browser that failed to open vs one that has not painted) and a matching heuristic ('Match on class, not title'). It lacks explicit when-not-to-use guidance and does not name window_action as the mutating alternative, but the context is clear.

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