diff --git a/lib/ci-helpers.sh b/lib/ci-helpers.sh
index 84c9503..e24dfc8 100644
--- a/lib/ci-helpers.sh
+++ b/lib/ci-helpers.sh
@@ -1,4 +1,5 @@
 #!/usr/bin/env bash
+set -euo pipefail
 # ci-helpers.sh — Shared CI helper functions
 #
 # Source from any script: source "$(dirname "$0")/../lib/ci-helpers.sh"
diff --git a/lib/parse-deps.sh b/lib/parse-deps.sh
index c0c58b4..4c3bc85 100755
--- a/lib/parse-deps.sh
+++ b/lib/parse-deps.sh
@@ -1,4 +1,5 @@
 #!/usr/bin/env bash
+set -euo pipefail
 # parse-deps.sh — Extract dependency issue numbers from an issue body
 #
 # Usage:
diff --git a/supervisor/supervisor-poll.sh b/supervisor/supervisor-poll.sh
index bdc8529..da1cb97 100755
--- a/supervisor/supervisor-poll.sh
+++ b/supervisor/supervisor-poll.sh
@@ -1,4 +1,5 @@
 #!/usr/bin/env bash
+set -euo pipefail
 # supervisor-poll.sh — Supervisor agent: bash checks + claude -p for fixes
 #
 # Two-layer architecture: