diff --git a/modules/cells/README.md b/modules/cells/README.md
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+# Cell
+
+This module is responsible for inner-cell communication.
+
+
+## Celle messages
+
+```mermaid
+sequenceDiagram
+    
+    participant  Cell 'A'
+    create participant cellEndpoint
+    Cell 'A' ->>+cellEndpoint: send(message) to 'B'
+    
+    create participant CellMessageDispatcher
+    cellEndpoint ->>+CellMessageDispatcher:message
+    CellMessageDispatcher ->>+CellMessageDispatcher:find receiver
+    
+    participant  Cell 'B'
+    CellMessageDispatcher ->>+Cell 'B': messageArrived(message) from 'A'
+
+```
diff --git a/modules/cells/readme b/modules/cells/readme
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-a changed readme