device_control

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

With no annotations, the description carries the full burden, and it does disclose two genuinely useful behavioral traits: ROM-dependent support and that reboot/network changes may disconnect ADB. It omits other important behavior — whether reboot/shutdown are irreversible, what permissions or root are needed (despite a 'root' parameter defaulting to true), and what the tool returns on unsupported actions.

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 capability list is front-loaded and dense with no filler, and the two trailing caveat sentences each add distinct risk information. The enumeration is an unstructured comma list rather than grouped by domain, which slightly hurts scanability but wastes no words.

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?

An output schema exists, so return values need not be explained. For a 3-parameter, high-blast-radius control tool, though, the definition should say what 'value' expects per action and when root is required; those gaps remain after the (admittedly broad) action enumeration.

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 0%, so the description must compensate, and it does partially by enumerating the accepted action values (including the underscore naming convention). However 'value' — whose meaning clearly changes per action (brightness level, volume level, screen density, etc.) — and 'root' are given no semantics anywhere, leaving the caller to infer formats.

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 enumerates the concrete resource domains the tool manipulates (wifi/bluetooth/mobile_data/airplane_mode, brightness, rotation, volume, reboot/shutdown, etc.), which makes the scope of 'device_control' tangible rather than tautological. It never differentiates itself from overlapping siblings such as system_settings, press_key, or adb_command, so an agent must guess the boundary.

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 when-to-use or when-not-to-use guidance, and no named alternative for overlapping tasks (e.g. system_settings for settings changes, root_shell for raw commands). 'ROM support varies' is a caveat about reliability, not a selection rule.

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