device_list

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

The readOnlyHint annotation already establishes that this is a safe read operation. The description adds meaningful context by specifying that the output includes ADB authorization states, which is not trivial and helps the agent understand the tool's behavior. It does not discuss edge cases like no devices connected, but the added detail justifies a score above baseline.

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, well-structured sentence that starts with the action verb and immediately states the resource. Every word contributes to the meaning, with no redundancy. It is front-loaded and easy to parse.

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?

Given the tool's trivial complexity (no parameters, no output schema), the description provides sufficient context for an agent to know what the tool does and what kind of output to expect. It names the key output elements (devices and authorization states), making the tool adequately specified.

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 has zero parameters, so the schema and description naturally cover everything. The baseline for 0 parameters is 4, and there is no additional parameter semantics needed. The description does not need to explain parameters that do not exist.

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 uses the specific verb 'List' and clearly identifies the resource ('connected Android devices') and the scope ('their ADB authorization states'). This distinguishes it from sibling tools like device_info, which likely focuses on a single device, and mirror_status, which pertains to mirroring. The purpose is unambiguous.

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 description implies usage for enumerating connected devices, but it does not explicitly state when to choose this over alternatives like device_info, nor does it provide any situational guidance or exclusions. The user must infer that this is the go-to tool for a device list based on its name and description.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.