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+# Think-Tank Directory
+
+A designated space for personal content that lives outside the codebase but needs version control.
+
+## Purpose
+Store personal documents, notes, and drafts that:
+- Don't belong in code directories
+- Need to persist across development sessions
+- Require version control for safety
+
+## Location
+**Always use**: `/think-tank/` in the main repository
+**Never use**: Worktree locations (they're ephemeral)
+
+## What Belongs Here
+✓ Personal notes and brainstorming
+✓ Resume drafts and career documents
+✓ Learning notes and research
+✓ Project ideas and planning docs
+✓ Personal scripts or configurations
+
+## What Doesn't Belong Here
+✗ Code documentation (use `/docs/`)
+✗ Project-specific notes (use project directories)
+✗ Sensitive credentials (use `.bash_secrets`)
+✗ Generated files or build artifacts
+
+## Key Principle
+Think-tank content is personal workspace material. It's tracked by git but kept separate from the technical ecosystem of the dotfiles.
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