desktop

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

Annotations already declare readOnlyHint=true and openWorldHint=false, so safety is covered; the description adds non-obvious behavior: layers are compositor-tracked but may be transparent or dormant, `kind` is best-effort, and layer geometry is usable for region screenshots or clicks. That is real 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-loaded with the resource and what it contains, then the layer caveat, then the workflow directive — no wasted sentences. The middle sentence is dense and heavily nested, which slightly hurts scanability but every clause carries distinct information.

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?

An output schema exists, so return-shape detail is not needed; the description still covers snapshot contents, layer semantics, and the intended call-first workflow. For a parameterless, read-only snapshot tool, nothing an agent needs to invoke it correctly is missing.

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 takes zero parameters, so the baseline is 4. The description correctly implies a parameterless snapshot call and adds no misleading parameter claims.

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?

Opens with a specific verb+resource ('Semantic desktop snapshot') and enumerates exactly what it returns (monitors, workspaces, windows with address/class/title/geometry, active window, cursor, layers). It also implicitly separates itself from the pixel-based `screenshot` sibling by stressing addresses and layer semantics rather than images.

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?

'Call first; act on the addresses it returns' gives explicit ordering guidance, and 'screenshot when visibility matters' names the alternative tool and the condition that selects it. An agent knows both when to reach for this tool and when to fall back to `screenshot`.

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