diff --git a/cmd/entire/cli/integration_test/issue_411_ended_idle_test.go b/cmd/entire/cli/integration_test/issue_411_ended_idle_test.go
new file mode 100644
index 0000000000..8e8574d35d
--- /dev/null
+++ b/cmd/entire/cli/integration_test/issue_411_ended_idle_test.go
@@ -0,0 +1,62 @@
+//go:build integration
+
+package integration
+
+import (
+	"testing"
+
+	"github.com/entireio/cli/cmd/entire/cli/session"
+	"github.com/stretchr/testify/require"
+)
+
+// TestIssue411_EndedToIdle_PrepareCommitMsgAddsTrailer is the natural
+// reproduction for https://github.com/entireio/cli/issues/411:
+// session-end (ENDED) → session-start (ENDED→IDLE) → new turn → git commit.
+// prepare-commit-msg must still attach Entire-Checkpoint.
+func TestIssue411_EndedToIdle_PrepareCommitMsgAddsTrailer(t *testing.T) {
+	t.Parallel()
+
+	env := NewFeatureBranchEnv(t)
+	sess := env.NewSession()
+
+	require.NoError(t, env.SimulateUserPromptSubmitWithPromptAndTranscriptPath(
+		sess.ID, "Initial work", sess.TranscriptPath))
+	env.WriteFile("first.go", "package main\n")
+	sess.CreateTranscript("Initial work", []FileChange{
+		{Path: "first.go", Content: "package main\n"},
+	})
+	require.NoError(t, env.SimulateStop(sess.ID, sess.TranscriptPath))
+
+	state, err := env.GetSessionState(sess.ID)
+	require.NoError(t, err)
+	require.NotNil(t, state)
+	require.Equal(t, session.PhaseIdle, state.Phase)
+
+	require.NoError(t, env.SimulateSessionEnd(sess.ID))
+	state, err = env.GetSessionState(sess.ID)
+	require.NoError(t, err)
+	require.NotNil(t, state)
+	require.Equal(t, session.PhaseEnded, state.Phase)
+
+	// Reported trigger: SessionStart after ENDED (ended → idle).
+	out := env.SimulateSessionStartWithOutput(sess.ID)
+	require.NoError(t, out.Err)
+	state, err = env.GetSessionState(sess.ID)
+	require.NoError(t, err)
+	require.NotNil(t, state)
+	require.Equal(t, session.PhaseIdle, state.Phase)
+	require.Nil(t, state.EndedAt)
+
+	require.NoError(t, env.SimulateUserPromptSubmitWithPromptAndTranscriptPath(
+		sess.ID, "Work after restart", sess.TranscriptPath))
+	env.WriteFile("second.go", "package main\n\nfunc Second() {}\n")
+	sess.CreateTranscript("Work after restart", []FileChange{
+		{Path: "second.go", Content: "package main\n\nfunc Second() {}\n"},
+	})
+	require.NoError(t, env.SimulateStop(sess.ID, sess.TranscriptPath))
+
+	env.GitCommitWithShadowHooks("Add second after ended→idle restart", "second.go")
+	cpID := env.GetCheckpointIDFromCommitMessage(env.GetHeadHash())
+	require.NotEmpty(t, cpID,
+		"prepare-commit-msg must add Entire-Checkpoint after ended→idle session restart (#411)")
+}