Stop then launch on displays

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

Annotations cover the safety profile (readOnlyHint=false, destructiveHint=false, idempotentHint=false), so the bar is lower. The description adds real behavioral detail beyond them: the stop-then-launch ordering, per-display iteration "in order", and that it is a forced (not graceful) stop. It omits any permission/auth notes or what state is lost on the force-stop.

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?

Two tight sentences with the action and sequencing front-loaded; every clause earns its place and no filler is present.

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 described, and annotations carry the safety profile. The main gap is the low schema coverage on userId and settleMs, which the description does not compensate for.

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 only 17%, so the description carries weight here. It touches packageName, activity ("main (or given) activity") and displayIds scope, but adds no meaning for serial, userId, or settleMs, whose defaults and constraints live only in the schema.

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?

States a specific compound action (force-stop then launch) applied to a named resource (package/activity) across a scoped target (each logical display). It clearly distinguishes itself from siblings mobile_app_launch and mobile_app_stop by the ordered multi-display sequence.

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?

"Use for dual-display cold-start / flash reproduction" gives explicit context for selecting this tool over plain launch/stop. It does not state when not to use it or name an alternative for single-display cold starts, so it falls short of the top band.

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