Set Orientation

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

Annotations declare readOnlyHint=false and destructiveHint=false, indicating a non-destructive mutation. The description says 'Change', which aligns with these annotations and adds no contradiction. However, it does not provide additional behavioral context such as side effects, timing, or device requirements beyond what the annotations imply. With annotations covering the safety profile, the description adds minimal extra value.

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 description is a single, succinct sentence that is easy to parse. It is not overly verbose, though it borders on being a slight restatement of the title. Still, it is appropriately sized for a simple tool with no wasted 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?

For a simple tool with only two well-documented parameters and no output schema, the description is adequate. The schema covers parameter semantics and the annotations cover safety. The description provides enough to understand the tool's purpose. One could argue it should mention that the change affects a physical device or simulator, but that is implied by the tool family and the device parameter guidance. Overall, the definition is sufficiently complete for an agent to call it correctly.

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 100%, meaning both parameters (device and orientation) are fully documented in the schema, including the orientation enum and the device instruction to list available devices. The description itself adds no parameter-specific information. Given the high schema coverage, a baseline of 3 is appropriate.

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 clear verb ('Change') and resource ('screen orientation'), and it naturally distinguishes itself from the sibling mobile_get_orientation (which reads orientation). It is specific and immediately conveys the tool's core action.

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 provides no guidance on when to use this tool versus alternatives. It does not mention that it should be used when an orientation change is needed, nor does it note that mobile_get_orientation is the read counterpart. The device parameter's schema description points to mobile_list_available_devices, but that is in the schema, not the description. Thus, usage context is only implied.

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