Xcode-Studio-MCP

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

With no annotations provided, the description carries the full burden. It successfully discloses the external dependency (idb) and output format (JSON), but lacks disclosure of read-only safety, error conditions (e.g., simulator not running), or the structure of the returned accessibility tree.

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?

Three sentences with zero waste: first defines the core function, second explains the value proposition, third states the hard prerequisite. Perfectly front-loaded and appropriately sized for the tool's complexity.

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?

Adequate for a single-parameter inspection tool, but lacks description of the JSON output structure since no output schema exists. Given the domain-specific nature of 'accessibility tree,' some description of the returned hierarchy or element properties would strengthen agent effectiveness.

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%, fully documenting the simulator_udid parameter including its default behavior. The description does not explicitly discuss parameters, but the schema is self-sufficient, making the baseline score of 3 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 clearly states the specific action (Get), resource (accessibility tree), format (JSON), and scope (current iOS Simulator screen). It effectively distinguishes from siblings like simulator_screenshot (visual) and simulator_tap/type (interaction) by emphasizing UI element discovery.

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?

Provides valuable prerequisite information ('Requires idb') and contextual usage guidance ('Useful for finding UI elements to interact with'), implying it should be used before tap/type operations. Could be improved by explicitly contrasting with simulator_screenshot for debugging strategies.

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