list-devices

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

With no annotations, the description carries the full behavioral burden and delivers extensively: it discloses return shape ({ devices, avds }), platform discriminators, states (running/stopped/connected/paired), headless behavior for additional CoreSimulator devices, silent omission of platforms with unavailable CLIs, and empty-result meaning. No annotation contradiction.

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?

Although long, the description is front-loaded with the core purpose and usage, then organized in clear platform-specific paragraphs. Each sentence adds operational detail (discovery mechanism, state semantics, alternatives) rather than filler, so the length is justified.

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?

This is a complex multi-platform inventory tool with no output schema or annotations, and the description covers all the context an agent needs: return format, target-id selection, per-platform behaviors, prerequisites, state/ordering semantics, and failure interpretation. It is effectively self-contained.

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 and schema coverage is 100%, so the baseline is 4; there are no parameter semantics to document. The description instead adds meaning to the returned fields (udid/serial/id, kind, state, runtimeKind), which is more relevant than parameter docs.

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 opening sentence states a precise verb ('List') with an explicit resource scope: iOS simulators, Android emulators, connected physical Android devices, running Chromium apps, and Vega/Fire TV devices. It also distinguishes the tool from interaction-focused siblings like boot-device and tv-remote by saying it returns target ids to pass to 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?

The description explicitly says to use it at the start of a session to pick a target id and see running targets. It names alternatives and conditions: use boot-device to boot stopped Vega devices and AVDs, no boot-device needed for physical phones, boot-device with electronAppPath for Chromium, and tv-remote/keyboard/describe for TV targets instead of gestures.

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