Lists accounts registered on an Android phone or emulator, returning each account name and type so AI agents can identify available Google identities before operating Gmail, Calendar, or Drive.
Accounts registered on the phone (name and type).
| Name | Required | Description | Default |
|---|---|---|---|
No arguments | |||
Changes observed during successful MCP inspections.
v0.1.0Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
No annotations exist, so the description carries the full burden; it does disclose the returned shape (name and type), which is useful. However it says nothing about whether an unlocked device or GET_ACCOUNTS-style permission is required, whether results include all account types, or what happens when no accounts exist.
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 short, front-loaded sentence with no waste. It is arguably terse to the point of under-specification, but nothing in it is 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?
For a zero-parameter tool with no output schema, the description should explain what comes back, and it only minimally does so (name and type). It omits account type semantics (e.g. Google vs Exchange) and any indication of result ordering or volume, leaving the agent to discover return details at call time.
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 tool takes zero parameters, so there is nothing for the description to disambiguate and the baseline of 4 applies. The schema is empty and consistent with a simple read of phone state.
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?
Names the specific resource (accounts registered on the phone) and the fields exposed (name and type), which distinguishes it from file-listing siblings like device_ls and state siblings like device_status. The verb is implicit rather than stated (it presumably lists/returns accounts), which keeps it short of 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?
There is no guidance on when to call this versus device_status, device_ls, or any other device-inspection tool, and no stated preconditions such as the device being unlocked or the required account permissions. The agent must infer usage entirely from the name.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.