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Systematic troubleshooting for Vision framework issues: subjects not detected, missing landmarks, low confidence, performance problems, coordinate mismatches, text recognition failures, barcode detection issues, and document scanning problems.

Symptom-based troubleshooting for Core Location issues.

Foundation Models issues manifest as context window exceeded errors, guardrail violations, slow generation, availability failures, and unexpected output. Core principle 80% of Foundation Models problems stem from misunderstanding model capabilities (3B parameter device-scale model, not world knowledge), context limits (4096 tokens), or availability requirements—not framework bugs.

Core principle 85% of networking problems stem from misunderstanding connection states, not handling network transitions, or improper error handling—not Network.framework defects.

Systematic troubleshooting for AVFoundation camera issues: frozen preview, wrong rotation, slow capture, session interruptions, and permission problems.

Core principle 85% of navigation problems stem from path state management errors, view identity issues, or placement mistakes—not SwiftUI defects.

Core principle 90% of cloud sync problems stem from account/entitlement issues, network connectivity, or misunderstanding sync timing—not iCloud infrastructure bugs.

Systematic diagnosis for common Metal porting issues.

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Symptom-based troubleshooting for background task issues.