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

No annotations are supplied, but the description discloses key runtime behavior: automatic CREATE on first call with a 250ms delay, signed relative deltas, and button bitmask encoding. It doesn't cover return values or click release semantics, but it provides materially useful behavioral detail.

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?

Three sentences, front-loaded with the action, with protocol and timing details kept compactly. No filler, no repetition, every sentence earns its place.

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?

The auto-CREATE behavior, protocol identifier, and relative-coordinate/button semantics cover what an agent needs to invoke it correctly. Since wheel/hWheel are already fully documented in the schema, their absence from the description is not a significant gap; output details are also not critical for this fire-and-forget input tool.

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 coverage is 100%, so the schema already documents all six parameters and their ranges. The description's dx/dy and bitmask notes mostly restate schema content rather than adding new meaning.

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 opening sentence names the exact verb ('Move') and resource ('virtual mouse'), and the second identifies hardware HID mouse id=1, which distinguishes it from touch-based uhid siblings like device_uhid_tap or device_uhid_swipe.

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 clearly identifies the tool's mechanism (hardware mouse via HID), but it never explicitly says when to prefer this over the touch/uhid siblings or lists exclusions. The usage context is implied rather than stated as a decision rule.

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