Simulate a mouse drag from a start to an end point over a set number of frames. Configure button and step count for precise control.
Drag mouse between two points over N frames
| Name | Required | Description | Default |
|---|---|---|---|
| toX | Yes | End X coordinate | |
| toY | Yes | End Y coordinate | |
| fromX | Yes | Start X coordinate | |
| fromY | Yes | Start Y coordinate | |
| steps | No | Number of frames for the drag. Default: 10 | |
| button | No | Mouse button (1=left). Default: 1 |
Changes observed during successful MCP inspections.
v1.0.0Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
No annotations are present, so the description carries the full burden of behavioral disclosure. It reveals that the drag is animated 'over N frames', but it does not state the fundamental drag lifecycle — whether the button is pressed at the start, held during movement, and released at the end — nor whether coordinates are screen-relative. For a drag operation this lifecycle is the core behavior an agent needs to understand.
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?
A single ten-word sentence that is verb-first and front-loads the essential scoping ('Drag mouse between two points over N frames'). Every word earns its place; there is zero redundancy or filler.
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 plus a well-covered schema is sufficient to make a syntactically correct call, but with no annotations and no output schema, key behavioral context is missing — the press-hold-release semantics, coordinate system, and relationship to sibling input tools. An agent can invoke it correctly but cannot predict the side effects or whether it needs to chain other calls.
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 description coverage is 100%, so the baseline is 3. The phrases 'between two points' and 'over N frames' map conceptually to the from/to coordinate parameters and the steps parameter, but the description adds no meaning beyond what the schema already documents.
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?
States a specific verb ('Drag'), a resource (mouse), and the operation's scope ('between two points over N frames'). The term 'drag' inherently distinguishes it from sibling tools like game_mouse_move and game_click, though it doesn't explicitly name them or contrast with them.
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?
No guidance on when to use this tool versus closely related siblings such as game_mouse_move (move without button) or game_click (single click). No prerequisites, exclusions, or conditions are stated, so an agent must infer usage entirely from the tool name.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.