get_screenshotCapture a plain image of an Android or iOS device's current screen to inspect UI state, debug layouts, or verify actions.
Plain screenshot as an image.
This tool declares no required parameters. Add optional parameters from the input schema as needed.
{
"id": 1,
"jsonrpc": "2.0",
"method": "tools/call",
"params": {
"arguments": {},
"name": "get_screenshot"
}
}| Name | Required | Description | Default |
|---|---|---|---|
| device | 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 of behavioral disclosure. It only says the result is an image; it does not mention permissions, device applicability, side effects, failure modes, or whether the screenshot reflects the current screen. This is minimal disclosure for an unannotated tool.
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 short and front-loaded with its main point, but it is under-specified rather than appropriately concise. The single sentence sacrifices essential usage and parameter information for brevity.
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 tool with one parameter, no output schema, and no annotations, the description should explain the device parameter and distinguish the tool from similar screenshot siblings. It does neither, leaving the agent without enough information to invoke the tool correctly.
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 one optional device parameter with 0% schema description coverage, and the description does not mention this parameter at all. The description completely fails to explain what device means, how it should be specified, or what the default behavior is.
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 that the tool produces a screenshot as an image, giving the agent the resource and output form. However, it does not distinguish get_screenshot from sibling tools like screenshot, screenshot_path, or browser_screenshot, so differentiation is left to inference.
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 is given about when to use this tool versus alternatives such as screenshot, perceive_screen, or read_screen. The word 'plain' weakly implies a raw image without analysis, but there is no explicit when-to-use or when-not-to-use guidance.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.