Fix macOS app PID selection to avoid helper processes

[gambit36]

Summary

• prefer the real foreground app process over helper/background processes
• avoid selecting helper, PlatformSupport, and Web Content processes when resolving app PIDs
• update the print_app_tree example to use the same selection logic

Why

When opening Safari, the previous bundle-id substring match could resolve to com.apple.SafariPlatformSupport.Helper instead of the main Safari app. That caused UI tree reads to miss the real window content.

Validation

• reproduced the issue with Safari selecting the helper process
• after this change, print_app_tree.py resolves the main Safari app and returns interactive elements from the real window

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Summary by cubic

Fixes macOS PID resolution to pick the main foreground app instead of helper/background processes, so UI tree reads target the actual window (e.g., Safari’s main process, not PlatformSupport.Helper).

• Bug Fixes
  • Added a scoring-based selector to prefer the primary app by name/bundle ID and penalize "Helper", "PlatformSupport", and "Web Content".
  • Integrated the selector in app launch flow and the print_app_tree.py example.
  • Verified with Safari: now resolves the main app PID and returns interactive elements from the real window.

^{Written for commit 16d710a. Summary will update on new commits.}

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[cubic-dev-ai]

1 issue found across 2 files

Prompt for AI agents (unresolved issues)

Check if these issues are valid — if so, understand the root cause of each and fix them. If appropriate, use sub-agents to investigate and fix each issue separately.


<file name="mlx_use/controller/service.py">

<violation number="1" location="mlx_use/controller/service.py:52">
P2: When scored selection returns `None`, fallback `pgrep` picks the first matching PID without helper/background filtering, reintroducing wrong app PID selection.</violation>
</file>

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[cubic-dev-ai]

P2: When scored selection returns None, fallback pgrep picks the first matching PID without helper/background filtering, reintroducing wrong app PID selection.

Prompt for AI agents

Check if this issue is valid — if so, understand the root cause and fix it. At mlx_use/controller/service.py, line 52:

<comment>When scored selection returns `None`, fallback `pgrep` picks the first matching PID without helper/background filtering, reintroducing wrong app PID selection.</comment>

<file context>
@@ -7,6 +7,50 @@
+		return None
+	scored.sort(key=lambda item: item[0], reverse=True)
+	best_score, best_app = scored[0]
+	return best_app if best_score > 0 else None
+
 from mlx_use.agent.views import ActionModel, ActionResult
</file context>