diff --git a/.opencode/rules/full-slot-migration-rule.md b/.opencode/rules/full-slot-migration-rule.md
index 7a01a8e9f8..a7459fa3b8 100644
--- a/.opencode/rules/full-slot-migration-rule.md
+++ b/.opencode/rules/full-slot-migration-rule.md
@@ -31,10 +31,112 @@ The `slot_fixes.yaml` file has been **manually curated** to specify the exact re
 - ✅ Follow the `revision` section TO THE LETTER
 - ✅ Use EXACTLY the slots and classes specified
 - ✅ Apply ALL components of the revision (both slots AND classes)
+- ✅ Interpret `link_branch` fields correctly (see below)
 - ✅ Update `processed.status: true` after completing migration
 
 ---
 
+## Understanding `link_branch` in Revision Plans
+
+🚨 **CRITICAL**: The `link_branch` field in revision plans indicates **nested class attributes**. Items with `link_branch: N` are slots/classes that belong TO the primary class, not standalone replacements.
+
+### How to Interpret `link_branch`
+
+| Revision Item | Meaning |
+|---------------|---------|
+| Items **WITHOUT** `link_branch` | **PRIMARY** slot and class to create |
+| Items **WITH** `link_branch: 1` | First attribute branch that the primary class needs |
+| Items **WITH** `link_branch: 2` | Second attribute branch that the primary class needs |
+| Items **WITH** `link_branch: N` | Nth attribute branch for the primary class |
+
+### Example: `visitor_count` Revision
+
+```yaml
+- original_slot_id: https://nde.nl/ontology/hc/slot/visitor_count
+  revision:
+    - label: has_or_had_quantity     # PRIMARY SLOT (no link_branch)
+      type: slot
+    - label: Quantity                 # PRIMARY CLASS (no link_branch)
+      type: class
+    - label: has_or_had_measurement_unit   # Quantity needs this slot
+      type: slot
+      link_branch: 1                        # ← Branch 1: unit attribute
+    - label: MeasureUnit                    # Range of has_or_had_measurement_unit
+      type: class
+      value:
+        - visitors
+      link_branch: 1
+    - label: temporal_extent               # Quantity needs this slot too
+      type: slot
+      link_branch: 2                        # ← Branch 2: time attribute
+    - label: TimeSpan                       # Range of temporal_extent
+      type: class
+      link_branch: 2
+```
+
+**Interpretation**: This creates:
+1. **Primary**: `has_or_had_quantity` slot → `Quantity` class
+2. **Branch 1**: `Quantity.has_or_had_measurement_unit` → `MeasureUnit` (with value "visitors")
+3. **Branch 2**: `Quantity.temporal_extent` → `TimeSpan`
+
+### Resulting Class Structure
+
+```yaml
+# The Quantity class should have these slots:
+Quantity:
+  slots:
+    - has_or_had_measurement_unit  # From link_branch: 1
+    - temporal_extent              # From link_branch: 2
+```
+
+### Complex Example: `visitor_conversion_rate`
+
+```yaml
+- original_slot_id: https://nde.nl/ontology/hc/slot/visitor_conversion_rate
+  revision:
+    - label: has_or_had_conversion_rate    # PRIMARY SLOT
+      type: slot
+    - label: ConversionRate                 # PRIMARY CLASS
+      type: class
+    - label: has_or_had_type               # ConversionRate.has_or_had_type
+      type: slot
+      link_branch: 1
+    - label: ConversionRateType            # Abstract type class
+      type: class
+      link_branch: 1
+    - label: includes_or_included          # ConversionRateType hierarchy slot
+      type: slot  
+      link_branch: 1
+    - label: ConversionRateTypes           # Concrete subclasses file
+      type: class
+      link_branch: 1
+    - label: temporal_extent               # ConversionRate.temporal_extent
+      type: slot
+      link_branch: 2
+    - label: TimeSpan                      # Range of temporal_extent
+      type: class
+      link_branch: 2
+```
+
+**Interpretation**:
+1. **Primary**: `has_or_had_conversion_rate` → `ConversionRate`
+2. **Branch 1**: Type hierarchy with `ConversionRateType` (abstract) + `ConversionRateTypes` (concrete subclasses)
+3. **Branch 2**: Temporal tracking via `temporal_extent` → `TimeSpan`
+
+### Migration Checklist for `link_branch` Revisions
+
+- [ ] Create/verify PRIMARY slot exists
+- [ ] Create/verify PRIMARY class exists
+- [ ] For EACH `link_branch: N`:
+  - [ ] Add the branch slot to PRIMARY class's `slots:` list
+  - [ ] Import the branch slot file
+  - [ ] Import the branch class file (if creating new class)
+  - [ ] Verify range of branch slot points to branch class
+- [ ] Update consuming class to use PRIMARY slot (not deprecated slot)
+- [ ] Update examples to show nested structure
+
+---
+
 ## Mandatory: Follow slot_fixes.yaml Revisions Exactly
 
 **The `revision` section in `slot_fixes.yaml` is AUTHORITATIVE.** Do not substitute different slots based on your own judgment.
diff --git a/AGENTS.md b/AGENTS.md
index 0dea8f16a1..f27acf5017 100644
--- a/AGENTS.md
+++ b/AGENTS.md
@@ -1603,6 +1603,43 @@ The `revision` section in `slot_fixes.yaml` specifies the EXACT slots and classe
 - ❌ Partially apply revisions
 - ❌ Add deprecation notes (keeping both old and new)
 
+**Understanding `link_branch` in Revisions**:
+
+The `link_branch` field indicates **nested class attributes**:
+
+| Revision Item | Meaning |
+|---------------|---------|
+| Items **WITHOUT** `link_branch` | PRIMARY slot and class to create |
+| Items **WITH** `link_branch: 1` | First attribute the primary class needs |
+| Items **WITH** `link_branch: 2` | Second attribute the primary class needs |
+
+**Example - `visitor_count` with `link_branch`**:
+
+```yaml
+- original_slot_id: https://nde.nl/ontology/hc/slot/visitor_count
+  revision:
+    - label: has_or_had_quantity     # PRIMARY SLOT
+      type: slot
+    - label: Quantity                 # PRIMARY CLASS
+      type: class
+    - label: has_or_had_measurement_unit   # Quantity.has_or_had_measurement_unit
+      type: slot
+      link_branch: 1                        # ← Branch 1
+    - label: MeasureUnit                    # Range of branch 1 slot
+      type: class
+      link_branch: 1
+    - label: temporal_extent               # Quantity.temporal_extent
+      type: slot
+      link_branch: 2                        # ← Branch 2
+    - label: TimeSpan                       # Range of branch 2 slot
+      type: class
+      link_branch: 2
+```
+
+**Interpretation**: Create `Quantity` class with TWO slots:
+- `has_or_had_measurement_unit` → `MeasureUnit` (branch 1)
+- `temporal_extent` → `TimeSpan` (branch 2)
+
 **Example - Following slot_fixes.yaml**:
 
 ```yaml