clo_ui_action

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

With no annotations, the description carries the full burden. It discloses that the snapshot token is consumed (one-shot behavior), enumerates supported actions, and includes a safety warning. It does not mention what the tool returns or error behavior, but for a UI input tool the core side effects and constraints are stated.

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?

The description is dense and information-packed, starting with a one-line summary and then mapping actions/constraints compactly. It loses a point because the dense run-together style makes some relationships (e.g., which parameters pair with which actions) require inference rather than explicit structure.

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 description covers the critical workflow requirement (fresh snapshot token), the action set, coordinate/element usage, modifiers, and keycodes. It doesn't explain parameter pairing (e.g., drag requires end coordinates) or return behavior, but the essential usage pattern for a UI action tool is mostly present.

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 descriptions are absent (0% coverage), but the description provides some parameter meaning: scroll uses y, ax_action requires an exposed value, key uses keycode, modifiers are listed. However, several parameters remain ambiguous: end_x/end_y (likely drag target), the difference between `value` for set_value vs text, and when element vs coordinates should be used.

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 this tool performs a UI action (one CLO-only UI action) and immediately provides the complete action vocabulary (press, set_value, ax_action, click, right_click, double_click, drag, key, text, scroll), which distinguishes it from sibling tools like snapshot or clo_status that capture or report state.

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 specifies the prerequisite ('Requires current snapshot token'), explains that 'state is consumed by an action', and warns against guessing coordinates or performing blind action sequences. It does not explicitly name alternative tools for other tasks, but the constraints are clear and actionable.

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