XcodeBuildMCP

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 mentions 'IMPORTANT: Requires projectPath and scheme' and gives an example, which adds some behavioral context (e.g., required inputs). However, it lacks details on what the build does (e.g., compiles code, produces an artifact), potential side effects (e.g., modifies files, requires Xcode), or error handling, which are critical for a build tool.

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 concise with two sentences: one stating the purpose and one with requirements and an example. It's front-loaded with the core action and device target, and the example adds practical value without unnecessary verbosity. However, the example could be slightly more informative (e.g., clarifying parameter types).

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 complexity (a build tool with 6 parameters, no annotations, and no output schema), the description is moderately complete. It covers the purpose and required inputs but lacks details on behavior (e.g., what happens during the build, output location), error cases, or how it differs from siblings. This leaves gaps for an agent to use it effectively in varied contexts.

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 schema description coverage is 100%, so the schema fully documents all 6 parameters. The description adds minimal value beyond the schema by emphasizing that 'projectPath' and 'scheme' are required, but it doesn't provide additional semantics like usage examples for other parameters (e.g., 'configuration' options). Baseline 3 is appropriate since the schema does the heavy lifting.

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 ('Builds an app') and target ('from a project file for a physical Apple device'), which is specific and actionable. However, it doesn't explicitly differentiate from sibling tools like 'build_dev_ws' or 'build_mac_proj', which likely target different build environments or project types.

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 by specifying 'for a physical Apple device' and listing required parameters, which provides some context. However, it doesn't explicitly state when to use this tool versus alternatives like 'build_sim_id_proj' (for simulators) or 'build_mac_proj' (for macOS), leaving the agent to infer from the 'device' keyword.

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