Xcode MCP Server

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

With no annotations provided, the description carries full burden but offers minimal behavioral insight. It states the action ('install') which implies a write operation, but doesn't disclose critical details like required permissions, whether installation is reversible, error conditions (e.g., invalid app bundle), or what happens on success/failure. For a mutation tool with zero annotation coverage, this is a significant gap in transparency.

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 directly states the tool's purpose without any fluff or redundancy. It is appropriately sized and front-loaded, with every word earning its place. No structural issues or unnecessary elaboration are present.

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 (a mutation operation with no annotations and no output schema), the description is incomplete. It lacks information about behavioral traits (e.g., side effects, error handling), prerequisites (e.g., simulator state), and output expectations. While the schema covers parameters well, the overall context for safe and effective use is insufficient for a tool that modifies system state.

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 both parameters ('device_id' and 'app_path') clearly documented in the schema. The description adds no additional meaning about parameters beyond what the schema provides (e.g., no format examples, constraints, or usage context). According to scoring rules, when schema coverage is high (>80%), the baseline is 3 even with no param info in the description.

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 ('install') and target ('app on a simulator'), which is specific and unambiguous. It distinguishes from sibling tools like 'xcode_launch_app_simulator' (which launches rather than installs) and 'xcode_install_app_device' (which installs on physical devices instead of simulators), though it doesn't explicitly name these alternatives in the description itself.

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 doesn't mention prerequisites (e.g., needing a booted simulator), exclusions (e.g., not for physical devices), or comparisons to siblings like 'xcode_install_app_device' or 'xcode_launch_app_simulator'. Usage is implied by the name but not explicitly stated.

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