status

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

With readOnlyHint=true and openWorldHint=false already declaring the safety profile, the description's added value is the idle_seconds signal and the associated 'don't steal the mouse' policy, which is genuine behavioral context. It says nothing about cost, latency, or freshness of the reported values, so it is useful but not rich.

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?

Two tight sentences: the first lists the returned signals, the second front-loads the actionable constraint. No filler and no repetition of the tool name.

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?

There is no output schema and no parameters, so the description carries the burden of explaining what comes back, which it largely does by enumerating the four fields and naming idle_seconds explicitly. It stops short of giving types or units (e.g. resolution format, idle_seconds granularity).

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?

Zero parameters, so the baseline is 4; there is no parameter meaning for the description to carry. The prose does describe the conceptual outputs (idle_seconds, foreground window), which partially substitutes for the absent output schema.

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 names the resource (machine status) and enumerates the specific fields returned: resolution, coordinate system, foreground window, and idle_seconds. This lets an agent separate it from sibling state-readers such as screenshot, windows, focus, and observe, though the opening is a bare noun phrase rather than an explicit verb.

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?

It gives an explicit when-to-use rule — check idle_seconds before acting — plus a concrete exclusion: don't take over the mouse while the user is actively using the computer. It doesn't name which sibling to call instead (e.g. observe or screenshot) when idle, so it falls short of full alternative routing.

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