diff --git a/e2e/entire/entire.go b/e2e/entire/entire.go
index 2a807412d3..d5d524660e 100644
--- a/e2e/entire/entire.go
+++ b/e2e/entire/entire.go
@@ -52,6 +52,14 @@ func Doctor(t *testing.T, dir string) string {
 	return run(t, dir, "doctor", "--force")
 }
 
+// DoctorOutput runs `entire doctor --force` and returns the captured
+// output, ignoring the exit code. Useful for preflight scans where the
+// caller wants to grep for specific findings without failing on
+// unrelated non-zero exits (e.g. v2 generation health drift).
+func DoctorOutput(dir string) (string, error) {
+	return runOutput(dir, "doctor", "--force")
+}
+
 // CleanDryRun runs `entire clean --dry-run` and returns the output.
 func CleanDryRun(t *testing.T, dir string) string {
 	t.Helper()
diff --git a/e2e/testutil/preflight_test.go b/e2e/testutil/preflight_test.go
new file mode 100644
index 0000000000..70a568ce23
--- /dev/null
+++ b/e2e/testutil/preflight_test.go
@@ -0,0 +1,57 @@
+package testutil
+
+import "testing"
+
+func TestFindHookDrift(t *testing.T) {
+	t.Parallel()
+
+	cases := []struct {
+		name      string
+		out       string
+		wantOK    bool
+		wantMatch string
+	}{
+		{
+			name:   "clean output passes",
+			out:    "✓ Metadata branches: OK\n✓ Codex hook trust: OK\nNo stuck sessions found.\n",
+			wantOK: false,
+		},
+		{
+			name:      "stale hooks file flagged",
+			out:       "Codex hooks: OUT OF DATE\n  1 hook(s) the CLI installs today aren't declared in .codex/hooks.json:\n",
+			wantOK:    true,
+			wantMatch: "OUT OF DATE",
+		},
+		{
+			name:      "trust review flagged",
+			out:       "Codex hook trust: REVIEW NEEDED\n  1 hook(s) declared in .codex/hooks.json have no trusted_hash entry yet:\n",
+			wantOK:    true,
+			wantMatch: "REVIEW NEEDED",
+		},
+		{
+			name:   "unrelated v2 generation issues do not trip preflight",
+			out:    "v2 generations: 3 issue(s) found\nError: v2 generation health check failed\n",
+			wantOK: false,
+		},
+		{
+			name:      "first matching marker wins",
+			out:       "Codex hooks: OUT OF DATE\n...\nCodex hook trust: REVIEW NEEDED\n",
+			wantOK:    true,
+			wantMatch: "OUT OF DATE",
+		},
+	}
+
+	for _, tc := range cases {
+
+		t.Run(tc.name, func(t *testing.T) {
+			t.Parallel()
+			marker, ok := findHookDrift(tc.out)
+			if ok != tc.wantOK {
+				t.Fatalf("findHookDrift returned ok=%v, want %v\noutput: %q", ok, tc.wantOK, tc.out)
+			}
+			if marker != tc.wantMatch {
+				t.Fatalf("findHookDrift returned %q, want %q", marker, tc.wantMatch)
+			}
+		})
+	}
+}
diff --git a/e2e/testutil/repo.go b/e2e/testutil/repo.go
index 1f363a9eea..e091b4cf9f 100644
--- a/e2e/testutil/repo.go
+++ b/e2e/testutil/repo.go
@@ -179,9 +179,49 @@ func SetupRepo(t *testing.T, agent agents.Agent) *RepoState {
 		}
 	})
 
+	verifyDoctorClean(t, dir, artDir)
+
 	return state
 }
 
+// hookDriftMarkers are doctor output substrings that signal an
+// actionable hook-installation problem. Scoped narrowly so unrelated
+// findings (e.g. v2 generation health on dev machines) don't trip
+// preflight.
+var hookDriftMarkers = []string{
+	"OUT OF DATE",   // codex hooks.json missing a canonical event
+	"REVIEW NEEDED", // codex hook trust gap
+}
+
+// verifyDoctorClean runs `entire doctor --force` and fails the test if
+// the output contains any hook-drift marker. The full output is dumped
+// to <artDir>/doctor-preflight.log either way so failure traces include
+// the diagnosis. Run after `entire enable` and any agent-specific
+// post-enable tweaks — drift here means the test would fail later in
+// confusing ways.
+func verifyDoctorClean(t *testing.T, dir, artDir string) {
+	t.Helper()
+	out, _ := entire.DoctorOutput(dir)
+	if artDir != "" {
+		_ = os.WriteFile(filepath.Join(artDir, "doctor-preflight.log"), []byte(out), 0o644)
+	}
+	if marker, ok := findHookDrift(out); ok {
+		t.Fatalf("preflight: entire doctor reports hook drift (%q):\n%s", marker, out)
+	}
+}
+
+// findHookDrift returns the first hookDriftMarkers substring present in
+// out, or "" + false when none match. Pulled out so the marker contract
+// is unit-testable without spawning the entire binary.
+func findHookDrift(out string) (string, bool) {
+	for _, marker := range hookDriftMarkers {
+		if strings.Contains(out, marker) {
+			return marker, true
+		}
+	}
+	return "", false
+}
+
 // ApplySuiteCheckpointsMode configures an arbitrary repo for the current
 // suite-wide E2E checkpoints mode. Useful for repos created outside SetupRepo,
 // such as fresh clones in remote-resume scenarios.