Simulate pressing the back button on an Android device via ADB to navigate backward in apps and system UI.
Press the back button
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": "adb_press_back"
}
}| Name | Required | Description | Default |
|---|---|---|---|
| deviceId | No | Target device ID (optional) |
Changes observed during successful MCP inspections.
v1.0.0Does 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 states the action without explaining side effects (e.g., navigating back, closing dialog, exiting app) or behavior when no deviceId is provided.
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 a single, clear sentence with no redundant words. It is appropriately sized for the simplicity of the action.
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 tool is simple (one optional param, no output schema), so the description is minimally viable. However, it lacks usage context and does not differentiate from similar key-press tools, which are gaps for an agent selecting the right tool.
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%, with deviceId described as 'Target device ID (optional)'. The description adds no additional parameter meaning beyond the schema, so the baseline of 3 applies.
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 'Press the back button' uses a specific verb and resource, clearly identifying the action. It distinguishes from siblings like adb_press_home and adb_press_key by specifying the back button.
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 provided on when to use this tool versus alternatives like adb_press_key or adb_press_home. The description gives no context for device selection or interaction with other navigation tools.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.