Touch Eden Screen

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

The description adds useful behavioral context beyond the destructiveHint annotation by explaining that coordinates are in screenshot pixel space and that source_width/source_height, if omitted, default to the current render size. This informs the agent about scaling behavior. It does not contradict the annotation, and the annotation already signals potential destructiveness.

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 three sentences, front-loaded with the primary purpose, then lists actions, and finally provides parameter nuance. Each sentence adds value without redundancy or fluff.

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?

Given the tool's complexity (10 parameters, output schema, destructive annotation), the description covers the core interaction, action types, and important coordinate scaling behavior. It omits details on multi-touch or duration semantics, but the output schema likely covers return values, and the essential usage is clear enough for an agent to invoke the tool correctly in common scenarios.

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 input schema has 0% description coverage, so the description must compensate. It explains end_x/end_y for swipes and clarifies the meaning of source_width/source_height. Other parameters (finger_id, session_id, duration_ms) remain unexplained, and while x/y are self-evident, the partial coverage leaves gaps.

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 states the tool's function clearly: 'Touch Eden at screenshot pixel coordinates.' It lists supported actions (tap, long_press, swipe, down, move, up), which distinguishes it from sibling input tools like eden_press_key or eden_run_input_script. The verb 'Touch' combined with the resource and coordinate system makes the purpose unambiguous.

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 provides implicit usage context: it handles touch gestures with coordinates, and gives specific guidance for swipe (end_x/end_y) and source dimensions. However, it does not explicitly state when to prefer this tool over alternatives or mention any exclusions, leaving the when-to-use mostly implied.

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