iOS Debugger Agent

Overview

Use XcodeBuildMCP to build and run the current project scheme on a booted iOS simulator, interact with the UI, and capture logs. Prefer the MCP tools for simulator control, logs, and view inspection.

When to Use

• When the user asks to run, debug, or inspect an iOS app on a simulator.
• When you need simulator UI interaction, screenshots, or runtime logs via XcodeBuildMCP.

Core Workflow

Follow this sequence unless the user asks for a narrower action.

1) Discover the booted simulator

• Call mcp__XcodeBuildMCP__list_sims and select the simulator with state Booted.
• If none are booted, ask the user to boot one (do not boot automatically unless asked).

2) Set session defaults

• Call mcp__XcodeBuildMCP__session-set-defaults with:
  • projectPath or workspacePath (whichever the repo uses)
  • scheme for the current app
  • simulatorId from the booted device
  • Optional: configuration: "Debug", useLatestOS: true

3) Build + run (when requested)

• Call mcp__XcodeBuildMCP__build_run_sim.
• If the build fails, check the error output and retry (optionally with preferXcodebuild: true) or escalate to the user before attempting any UI interaction.
• After a successful build, verify the app launched by calling mcp__XcodeBuildMCP__describe_ui or mcp__XcodeBuildMCP__screenshot before proceeding to UI interaction.
• If the app is already built and only launch is requested, use mcp__XcodeBuildMCP__launch_app_sim.
• If bundle id is unknown:
  1. mcp__XcodeBuildMCP__get_sim_app_path
  2. mcp__XcodeBuildMCP__get_app_bundle_id

UI Interaction & Debugging

Use these when asked to inspect or interact with the running app.

• Describe UI: mcp__XcodeBuildMCP__describe_ui before tapping or swiping.
• Tap: mcp__XcodeBuildMCP__tap (prefer id or label; use coordinates only if needed).
• Type: mcp__XcodeBuildMCP__type_text after focusing a field.
• Gestures: mcp__XcodeBuildMCP__gesture for common scrolls and edge swipes.
• Screenshot: mcp__XcodeBuildMCP__screenshot for visual confirmation.

Logs & Console Output

• Start logs: mcp__XcodeBuildMCP__start_sim_log_cap with the app bundle id.
• Stop logs: mcp__XcodeBuildMCP__stop_sim_log_cap and summarize important lines.
• For console output, set captureConsole: true and relaunch if required.

Troubleshooting

• If build fails, ask whether to retry with preferXcodebuild: true.
• If the wrong app launches, confirm the scheme and bundle id.
• If UI elements are not hittable, re-run describe_ui after layout changes.

Example

User request:

Run, debug, or inspect an iOS app on a simulator.

Limitations

• Use this skill only when the task clearly matches the scope described above.
• Do not treat the output as a substitute for environment-specific validation, testing, or expert review.
• Stop and ask for clarification if required inputs, permissions, safety boundaries, or success criteria are missing.