Install an app bundle

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

No annotations are provided, so the description must carry the full burden of behavioral disclosure. The description reveals that it relies on xcrun simctl install but does not disclose potential side effects (e.g., replacing an existing app, requiring the simulator to be booted). It also doesn't mention whether it automatically boots a simulator or if the user must ensure it's running. This is a moderate gap for a state-changing operation.

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 two sentences long, front-loaded with the core purpose, and directly states the use context. Every sentence contributes useful information without fluff. Excellent conciseness.

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?

The tool is a two-parameter, straightforward installation routine with no output schema. The description covers the main context (after build or locating bundle) and the mechanism. It could benefit from noting prerequisites like simulator being booted, but given the simplicity and the clear schema, it is nearly complete.

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 input schema already provides 100% coverage of both parameters, so the baseline is 3. The description adds minimal extra value about the parameters (though it does mention 'after locating a derived-data app bundle' which hints at the appPath). However, it does not clarify the format of the UDID beyond the UUID format in the schema. Given the schema is strong, the description's limited addition is acceptable; a 4 is fair.

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 clearly states the specific verb (Install), the resource (.app bundle), and the mechanism (xcrun simctl install). It explicitly mentions the target context (simulator) and differentiates from sibling tools that launch, terminate, or build apps.

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 clear when-to-use guidance (after build_project or after locating a derived-data app bundle). It does not explicitly exclude alternatives, but the sibling list includes launch_app and terminate_app, and the description does not confuse install with those. It lacks an explicit 'do not use for' statement but is otherwise sufficiently contextual.

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