List phones

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

readOnlyHint=true already tells the agent this is a safe read with no side effects, so the description's remaining job is small. It does add useful context by saying the result covers both connected devices and available device profiles, but nothing about format, emptiness handling, or whether profiles are per-device.

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?

One short sentence with no filler, and the resource is stated up front. It is slightly compressed — 'available device profiles' never gets clarified — but nothing is wasted.

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, read-only list call this is close to complete, and no output schema exists to defer to. However, the description does not say what a 'device profile' is or how the two result sets relate, which is the main thing an agent would need before calling.

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 schema has zero parameters, so the baseline of 4 applies; there is no parameter semantics for the description to compensate for.

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 names a specific verb ('Show') and the resources it covers: connected devices and available device profiles, which matches the 'phone_list' name. It is clearly a read/list operation against the sibling tools, which are all actions (tap, install, start), but it never explicitly contrasts itself with any of them.

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?

Usage is only implied — an agent can guess you call this to discover devices/profiles before acting, but the description states no when-to-use condition and names no alternative. For a zero-parameter discovery tool the inference is easy, which keeps this above a 2.

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