# LeadPilot — Lead Activity Timeline Architecture

**Document Version:** 1.0.0 (Phase 7 Lead Management Lock)  
**Status:** Implemented & Verified  

---

## 1. Immutable Event Types Catalog

All domain mutations within the Lead Management module generate append-only chronological entries in `lead_activities`:

```
+------------------------+-------------------------------------------------------------------------------------+
| EVENT TYPE             | TRIGGERING OPERATION & DESCRIPTION                                                  |
+------------------------+-------------------------------------------------------------------------------------+
| `lead_created`         | Generated on manual or webhook lead creation.                                       |
| `stage_changed`        | Generated when lead moves to another pipeline stage (`old_value` -> `new_value`).   |
| `lead_assigned`        | Generated when lead assignee changes to a new workspace rep.                        |
| `note_added`           | Generated when an internal note is recorded by a team member.                       |
| `lead_archived`        | Generated when lead is archived out of active views.                                |
| `lead_won`             | Generated when lead transitions to terminal Won stage.                              |
| `lead_lost`            | Generated when lead transitions to terminal Lost stage with reason & notes.         |
+------------------------+-------------------------------------------------------------------------------------+
```