Xcode MCP Server

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

No annotations are provided, so the description carries the full burden. It states the action ('Shuts down') but lacks details on behavioral traits such as whether this is destructive, requires specific permissions, or has side effects (e.g., stopping associated processes). This is a significant gap for a mutation tool with no annotation coverage.

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, efficient sentence that front-loads the core purpose without unnecessary words. Every part of the sentence contributes directly to understanding the tool's function, making it appropriately sized and well-structured.

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 mutation with one parameter) and no annotations or output schema, the description is minimally adequate. It covers the basic action and parameter but lacks completeness in behavioral context, such as error handling or return values, which would be needed for full agent understanding.

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%, with the parameter 'udid' fully documented in the schema. The description adds no additional meaning beyond what the schema provides, such as format examples or constraints, so it meets the baseline for high coverage without compensating value.

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 ('Shuts down') and target resource ('an active iOS simulator'), distinguishing it from sibling tools like 'boot_simulator' and 'list_simulators'. It precisely identifies the verb and resource without ambiguity.

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 implies usage context by specifying 'an active iOS simulator', suggesting it should be used when a simulator is running. However, it does not explicitly state when not to use it or name alternatives like 'boot_simulator' for starting simulators, leaving some guidance gaps.

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