diff --git a/internal/calendar/scheduler.go b/internal/calendar/scheduler.go
index 2a82a79..f594130 100644
--- a/internal/calendar/scheduler.go
+++ b/internal/calendar/scheduler.go
@@ -158,6 +158,9 @@ func (s *Scheduler) tickForAgent(ctx context.Context, agent ReportableAgent, now
 			chosen = slot
 		}
 	}
+	s.host.Log("info", "calendar slot selection", map[string]any{
+		"agent": agent.ID, "available": len(resp.Slots), "chosen": chosen != nil,
+	})
 	if chosen != nil {
 		s.dispatchSlot(ctx, agent.ID, *chosen)
 	}
@@ -173,14 +176,19 @@ func (s *Scheduler) tickForAgent(ctx context.Context, agent ReportableAgent, now
 // transition immediately.
 func (s *Scheduler) dispatchSlot(ctx context.Context, agentID string, slot Slot) {
 	ident := slot.SlotIdent()
+	s.host.Log("info", "calendar dispatchSlot enter", map[string]any{
+		"agent": agentID, "slot_ident": ident,
+	})
 	s.mu.Lock()
 	if _, dup := s.activeBySlotIdent[ident]; dup {
 		s.mu.Unlock()
+		s.host.Log("info", "calendar dispatchSlot skipped (already active)", map[string]any{"slot": ident})
 		return
 	}
 	if _, agentBusy := s.activeByAgentID[agentID]; agentBusy {
 		// Don't pick up another slot until the current one resolves.
 		s.mu.Unlock()
+		s.host.Log("info", "calendar dispatchSlot skipped (agent has active slot)", map[string]any{"agent": agentID})
 		return
 	}
 	now := time.Now().UTC()
@@ -191,12 +199,21 @@ func (s *Scheduler) dispatchSlot(ctx context.Context, agentID string, slot Slot)
 
 	message := buildWakeMessage(slot)
 	source := "calendar:" + ident
+	s.host.Log("info", "calendar firing WakeAgent", map[string]any{
+		"agent": agentID, "slot": ident, "source": source, "msg_len": len(message),
+	})
 	if err := s.host.WakeAgent(ctx, sdkplugin.WakeAgentRequest{
 		AgentID: agentID, Message: message, Source: source,
 	}); err != nil {
+		s.host.Log("warn", "calendar WakeAgent failed", map[string]any{
+			"agent": agentID, "err": err.Error(),
+		})
 		s.resolveLocally(ident, agentID, SlotAborted, "", "wake failed: "+err.Error())
 		return
 	}
+	s.host.Log("info", "calendar WakeAgent enqueued ok", map[string]any{
+		"agent": agentID, "slot": ident,
+	})
 	// Mark Ongoing on the backend.
 	update := SlotAgentUpdate{
 		Status: SlotOngoing, StartedAt: now.Format("15:04:05"),
diff --git a/internal/calendar/types.go b/internal/calendar/types.go
index aa8669c..5b1848f 100644
--- a/internal/calendar/types.go
+++ b/internal/calendar/types.go
@@ -8,16 +8,18 @@ package calendar
 import "time"
 
 // SlotStatus enumerates the lifecycle. String values match backend's
-// SlotStatus enum verbatim (camelCase as stored in DB).
+// SlotStatus enum verbatim (snake_case — verified via heartbeat
+// response shape against running harborforge-backend).
 type SlotStatus string
 
 const (
-	SlotNotStarted SlotStatus = "NotStarted"
-	SlotOngoing    SlotStatus = "Ongoing"
-	SlotFinished   SlotStatus = "Finished"
-	SlotAborted    SlotStatus = "Aborted"
-	SlotDeferred   SlotStatus = "Deferred"
-	SlotPaused     SlotStatus = "Paused"
+	SlotNotStarted SlotStatus = "not_started"
+	SlotOngoing    SlotStatus = "ongoing"
+	SlotFinished   SlotStatus = "finished"
+	SlotAborted    SlotStatus = "aborted"
+	SlotDeferred   SlotStatus = "deferred"
+	SlotPaused     SlotStatus = "paused"
+	SlotSkipped    SlotStatus = "skipped"
 )
 
 // SlotType: work vs on_call. Affects whether the agent flips to busy.