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+# Phase B1 Complete: Logic Builder Node Registration
+
+**Status:** ✅ Complete - Ready for Manual Testing
+
+**Date:** 2026-01-11
+
+---
+
+## What Was Accomplished
+
+### 1. IODetector Utility
+
+**File:** `packages/noodl-editor/src/editor/src/utils/IODetector.ts`
+
+- Scans Blockly workspace JSON for Input/Output blocks
+- Auto-detects inputs, outputs, signal inputs, and signal outputs
+- Supports both explicit definitions and implicit usage detection
+- Returns typed structure with port information
+
+### 2. Logic Builder Runtime Node
+
+**File:** `packages/noodl-runtime/src/nodes/std-library/logic-builder.js`
+
+**Features:**
+
+- Stores Blockly workspace as JSON parameter
+- Dynamically creates ports based on detected I/O
+- Executes generated JavaScript code
+- Provides full Noodl API context (Variables, Objects, Arrays)
+- Signal-triggered execution
+- Error handling and reporting
+
+**Inputs:**
+
+- `workspace` - JSON string of Blockly workspace
+- `generatedCode` - JavaScript generated from blocks
+- Dynamic inputs detected from workspace
+
+**Outputs:**
+
+- `error` - Error message if execution fails
+- Dynamic outputs detected from workspace
+- Dynamic signal outputs
+
+### 3. Node Registration
+
+- Added to `packages/noodl-runtime/noodl-runtime.js` in Custom Code section
+- Added to node picker under "Custom Code" category
+- Configured with proper metadata (color: 'javascript', category: 'CustomCode')
+
+---
+
+## Manual Testing Checkpoint
+
+### Test 1: Node Appears in Picker ✅ READY
+
+**Steps:**
+
+1. Run `npm run dev` to start the editor
+2. Open any project
+3. Click "Add Node" (or right-click canvas)
+4. Navigate to **Custom Code** category
+5. Look for "Logic Builder" node
+
+**Expected Result:**
+
+- Node appears in Custom Code section
+- Node has purple color (javascript category)
+- Node description: "Build logic visually with blocks"
+- Search tags work: "blockly", "visual", "logic", "blocks", "nocode"
+
+### Test 2: Node Can Be Added to Canvas ✅ READY
+
+**Steps:**
+
+1. Add "Logic Builder" node to canvas
+2. Check node appears with proper color/styling
+3. Check property panel shows node parameters
+
+**Expected Result:**
+
+- Node renders on canvas
+- Node has "workspace" parameter (string, allowEditOnly)
+- Node has "generatedCode" parameter (string)
+- Node inspector shows "Logic Builder" text
+
+### Test 3: Basic Functionality (Limited)
+
+**Note:** Full functionality requires Phase C (tab system) to be usable.
+
+**Current State:**
+
+- Node can be added
+- Parameters exist but aren't editable via UI yet
+- No tab system for visual editing yet
+- No dynamic ports yet (need workspace content)
+
+---
+
+## What's Next: Phase C - Tab System Prototype
+
+The next phase will add:
+
+1. **Canvas Tabs Component**
+
+   - Tab bar UI for switching views
+   - Active tab state management
+   - Tab close functionality
+
+2. **Blockly Integration in Tabs**
+
+   - "Edit Logic Blocks" button in property panel
+   - Opens Logic Builder workspace in new tab
+   - BlocklyWorkspace component renders in tab
+   - Tab shows live Blockly editor
+
+3. **State Management**
+   - Context API for tab state
+   - Persists workspace when switching tabs
+   - Handles multiple Logic Builder nodes
+
+**Estimated Time:** 2-3 hours
+
+---
+
+## Files Changed (7 files)
+
+**Created:**
+
+- `packages/noodl-editor/src/editor/src/utils/IODetector.ts`
+- `packages/noodl-runtime/src/nodes/std-library/logic-builder.js`
+
+**Modified:**
+
+- `packages/noodl-runtime/noodl-runtime.js`
+- `packages/noodl-runtime/src/nodelibraryexport.js`
+- `packages/noodl-editor/package.json` (added blockly dependency)
+
+**From Phase A:**
+
+- `packages/noodl-editor/src/editor/src/views/BlocklyEditor/*` (5 files)
+
+---
+
+## Git Commits
+
+```
+5dc704d - feat(blockly): Phase B1 - Register Logic Builder node
+554dd9f - feat(blockly): Phase A foundation - Blockly setup, custom blocks, and generators
+df4ec44 - docs(blockly): Update CHANGELOG for Phase A completion
+```
+
+---
+
+## Known Limitations (To Be Addressed)
+
+1. **No Visual Editor Yet** - Need tab system (Phase C)
+2. **No Dynamic Ports** - Requires workspace parameter to be set
+3. **No Code Generation Hook** - Need to wire Blockly → generatedCode
+4. **No Property Panel Integration** - "Edit Logic Blocks" button doesn't exist yet
+5. **No Tests** - Unit tests deferred to later phase
+
+---
+
+## Developer Notes
+
+### IODetector Pattern
+
+The IODetector scans block types:
+
+- `noodl_define_input` / `noodl_get_input` → inputs
+- `noodl_define_output` / `noodl_set_output` → outputs
+- `noodl_define_signal_input` / `noodl_on_signal` → signal inputs
+- `noodl_send_signal` / `noodl_define_signal_output` → signal outputs
+
+### Node Execution Pattern
+
+The Logic Builder node follows the pattern:
+
+1. Workspace JSON stored in parameter
+2. On workspace change → detect I/O → update dynamic ports
+3. Signal input triggers → generate code → execute in context
+4. Outputs updated → downstream nodes receive values
+
+### Integration Points
+
+For Phase C, we'll need to hook into:
+
+- Property panel to add "Edit Logic Blocks" button
+- Node graph editor to add tab system
+- Potentially NodeGraphEditor component for tab UI
+
+---
+
+## Questions for Manual Testing
+
+When you test, please note:
+
+1. Does the node appear in the correct category?
+2. Is the node color/styling correct?
+3. Can you add multiple instances?
+4. Does the inspector show correct info?
+5. Any console errors when adding the node?
+
+Please provide feedback before we proceed to Phase C!
+
+---
+
+**Next Step:** Run `npm run dev` and verify the node appears in the picker.