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

No annotations are provided, so the description carries the full burden. It discloses the crucial coordinate-space detail and notes that a left-to-right swipe is verified to behave like the `right` button. However, it does not mention potential side effects (e.g., whether the TV wakes, behavior when focus cannot move) or the effect of durationMs. Given the action is a low-risk focus movement, this is a strong disclosure but not exhaustive.

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, each with a distinct purpose: action, critical caveat, and usage recommendation. No filler or redundancy. The most important information (coordinate space) is front-loaded in the second sentence. Highly efficient.

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 focused swipe tool, the description covers the key aspects: what it does, coordinate system, verification, and when to prefer an alternative. The schema documents all parameters, so the description need not repeat them. Minor gaps include not explicitly mentioning that it is Apple TV–specific (though the name implies it) and not stating the effect of the `wake` parameter, but these are minor given the schema covers them.

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 each parameter is described. The description adds significant value by clarifying that startX/startY/endX/endY are in the touchpad's 0-1000 space, not screen pixels, which is essential for correct use. It also reinforces the purpose of durationMs indirectly by contrasting with single-step button presses. This goes beyond the schema's basic descriptions.

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 clearly states the verb ('Swipe'), the resource ('Apple TV remote's TOUCHPAD'), and the purpose ('to move focus'). It also distinguishes itself from ios_tv_button by explicitly mentioning the coordinate space and that it is for longer runs. This leaves no ambiguity about what the tool does.

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 explicitly says 'prefer ios_tv_button for single steps and use this for longer runs', giving clear guidance on when to use this tool versus its sibling. It also warns that coordinates are not screen pixels, preventing a common misuse. This is exemplary usage guidance.

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