Fold Device

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

Annotations already disclose that this is a non-read-only, non-destructive, closed-world operation, so the description need not repeat the safety profile. It adds useful context about foldable device types and the posture/angle input requirement, but stops short of describing failure modes, prerequisites such as device allocation, or the effect on device state beyond the fold itself.

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 sentences, front-loaded with the operation and followed by the key input constraint. The examples and instruction all earn their place without redundancy.

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 low complexity, rich parameter schema, and annotations covering the mutation profile, the description supplies enough context to call the tool correctly. It could be slightly stronger by clarifying whether one of posture/angle is mandatory, but the schema and description together cover the essentials.

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 coverage is 100%, so the schema already documents all three parameters in detail. The description adds a meaningful constraint not encoded in the required list: the caller must provide either posture or angle, which helps resolve the otherwise ambiguous optional parameters.

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 states a specific verb pair (fold/unfold) and resource (foldable device), with examples that make the scope immediately clear. It is distinguishable from siblings like mobile_set_orientation because it targets foldable hardware and hinge posture/angle rather than general screen orientation.

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?

It provides clear context by naming the device class (foldable simulators/emulators) and instructs the caller to provide either posture or angle. It does not explicitly name an alternative tool or state when not to use it, but the context is sufficient to guide selection.

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