diff --git a/internal/continuity/continuity.go b/internal/continuity/continuity.go
index 24cbbe8..746aac8 100644
--- a/internal/continuity/continuity.go
+++ b/internal/continuity/continuity.go
@@ -151,6 +151,12 @@ const maxAuthoredAction = 2*maxAuthoredLine + len(" — ")
 var circularAction = regexp.MustCompile(`(?i)handoff|report\.md|^continue the task`)
 var circularCommand = regexp.MustCompile(`(?i)\.orchestra-handoff|handoff-report|report\.md`)
 
+// IsCircularCommand reports whether Validate would reject this as a command
+// that points at a handoff. Producers need the same answer before they build a
+// handoff, so the rule lives in one place rather than being restated as a
+// second regexp that can drift.
+func IsCircularCommand(s string) bool { return circularCommand.MatchString(s) }
+
 func (h Handoff) Validate() error {
 	if strings.TrimSpace(h.Meta.ID) == "" || !reasons[h.Meta.Reason] || h.Meta.RotationIndex < 0 {
 		return errors.New("invalid handoff meta")
diff --git a/internal/herdr/adapter.go b/internal/herdr/adapter.go
index e6a57e4..7113d62 100644
--- a/internal/herdr/adapter.go
+++ b/internal/herdr/adapter.go
@@ -538,9 +538,19 @@ func (a CLIAdapter) lastObservedCommand(s Session) string {
 		return ""
 	}
 	for i := len(calls) - 1; i >= 0; i-- {
-		if calls[i].Kind == "command" {
-			return calls[i].Key
+		if calls[i].Kind != "command" {
+			continue
 		}
+		// Skip the write Orchestra itself asked for. The handoff prompt tells
+		// the agent to write HandoffReportFile and stop, so that write is
+		// almost always the last command in the pane. Carrying it into
+		// Handoff.Command made every rotation fail its own circularity check
+		// with "must not point to a handoff or report" (F37). The successor
+		// wants the last command that was real work.
+		if continuity.IsCircularCommand(calls[i].Key) {
+			continue
+		}
+		return calls[i].Key
 	}
 	return ""
 }
diff --git a/internal/herdr/adapter_test.go b/internal/herdr/adapter_test.go
index d930ca2..63d9d4e 100644
--- a/internal/herdr/adapter_test.go
+++ b/internal/herdr/adapter_test.go
@@ -334,3 +334,34 @@ func TestEveryReasonTheAdapterProducesIsAcceptedByTheValidator(t *testing.T) {
 		}
 	}
 }
+
+// TestLastObservedCommandSkipsOrchestrasOwnHandoffWrite guards F37. The handoff
+// prompt tells the agent to write HandoffReportFile and stop, so that write is
+// almost always the last command in the pane. Carrying it into Handoff.Command
+// made every rotation fail Validate's own circularity check. Live on run 5:
+// "adapter: upload handoff: invalid handoff command: must not point to a
+// handoff or report".
+func TestLastObservedCommandSkipsOrchestrasOwnHandoffWrite(t *testing.T) {
+	for _, last := range []string{
+		"cat > " + HandoffReportFile,
+		"vim .orchestra-handoff.json",
+		"less handoff-report.md",
+	} {
+		if !continuity.IsCircularCommand(last) {
+			t.Fatalf("%q is not recognised as circular, so this test proves nothing", last)
+		}
+		h := continuity.Handoff{
+			Meta:    continuity.Meta{ID: "agent-1", Reason: "phase_changed"},
+			Anchor:  continuity.Anchor{GitSHA: "0000000000000000000000000000000000000000", Branch: "main"},
+			Action:  "write the research note",
+			Command: "go test ./...",
+		}
+		if err := h.Validate(); err != nil {
+			t.Fatalf("a real command was rejected: %v", err)
+		}
+		h.Command = last
+		if err := h.Validate(); err == nil {
+			t.Fatalf("%q was accepted, so skipping it in the producer is not what keeps rotations alive", last)
+		}
+	}
+}