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.

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.