Capture the current screen to view the CapCut or Canva editor, with optional max width for scaling. Use this image to map real desktop pixel coordinates for other tools.
Take a screenshot of your screen (to see the CapCut/Canva editor). Coordinates for the other desktop tools are in real screen pixels: divide image coordinates by 'scale'.
| Name | Required | Description | Default |
|---|---|---|---|
| max_width | No |
Changes observed during successful MCP inspections.
v0.1.0Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
With no annotations, the description carries the full burden, and it does disclose one real behavioral trait: the image is scaled and a 'scale' divisor converts image coordinates to real screen pixels. It omits other relevant traits such as what format the screenshot is returned in, multi-monitor behavior, or any permission requirement, so it is only partially transparent.
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?
Two tight sentences with the core action front-loaded and no filler. The second sentence drifts slightly toward sibling-tool coordinate semantics, but it is directly derived from this tool's scaled output, so it still 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?
No annotations and no output schema mean the description must explain what comes back. It hints at a 'scale' value but never says where that value lives (it is not in the input schema or a documented return), and max_width is left unexplained, leaving the agent short of what it needs to use the output reliably.
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 schema has 0% description coverage for the single parameter max_width, and the description never mentions it or explains how it affects the output image. The only coordinate/scale discussion concerns a value that is not even a declared parameter, so the description fails to compensate for the coverage gap.
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+resource ('Take a screenshot of your screen') and even names the target context (the CapCut/Canva editor). No sibling offers screenshot capture, so differentiation is implicit rather than stated, which keeps it just under a 5.
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 parenthetical gives a concrete when-to-use trigger (inspecting the editor before interacting), and the second sentence tells the agent how to translate the returned image coordinates for the other desktop_* tools. No when-not guidance or explicit alternative is given, but for a single-purpose capture tool that is a minor gap.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.