Turn off the Android screen and re-lock the phone to reduce host CPU use after tasks; optionally return to the home screen first.
Turn the screen off (re-locks the phone). Use when done, to save CPU on the host.
| Name | Required | Description | Default |
|---|---|---|---|
| home | No | Go to the home screen first. |
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. It usefully discloses the screen-off effect, the re-lock side effect, and the CPU-saving rationale, but it omits whether the device must already be unlocked, what happens if it is already locked, and whether any confirmation is returned.
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 short sentences, zero wasted words, and the core effect is front-loaded before the usage guidance.
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 simple one-optional-parameter device action with no output schema, the description covers purpose, side effect, and timing. The schema handles the parameter detail; only minor behavioral edge cases remain unstated.
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 coverage is 100%, and the single home parameter is fully described in the schema. The description does not add any parameter meaning beyond the schema, so the baseline score of 3 is appropriate.
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 a specific verb and effect: turning the screen off and re-locking the phone. This clearly distinguishes it from the sibling device_unlock action and tells an agent exactly what the tool does.
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?
It gives clear usage context: use when done, to save CPU on the host. It does not name alternatives or exclusions, but the timing guidance is explicit.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.