Xcode MCP Server

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

With no annotations provided, the description carries the full burden of behavioral disclosure. It states the tool lists simulators but fails to describe key behaviors such as output format (e.g., structured vs. plain text), whether it's a read-only operation, potential side effects, or any performance considerations. This leaves significant gaps in understanding how the tool behaves.

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, direct sentence that efficiently conveys the core purpose without any unnecessary words. It is front-loaded and wastes no space, making it easy for an AI agent to parse quickly.

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 tool's complexity (simple listing operation) but lack of annotations and output schema, the description is incomplete. It doesn't explain what the output looks like (e.g., list format, data structure), which is critical for an AI agent to use the tool effectively. The absence of behavioral details further reduces completeness.

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 tool has 0 parameters, and the schema description coverage is 100%, so there are no parameters to document. The description appropriately doesn't mention parameters, which is correct for this case. A baseline of 4 is applied as it meets the expectation for a parameterless tool.

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 action ('List') and target resources ('all available iOS, watchOS, and tvOS simulators'), making the purpose immediately understandable. However, it doesn't explicitly differentiate from sibling tools like 'xcode_list_available_simulators' or 'xcode_list_simulators_json', which appear to serve similar purposes, preventing a perfect score.

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 like 'xcode_list_available_simulators' or 'xcode_list_simulators_json', nor does it mention any prerequisites or contexts for usage. This lack of comparative or contextual advice limits its utility for an AI agent.

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