diff --git a/ethereum/anvil_fork b/ethereum/anvil_fork
index 9d5044c181..ad9644782d 100755
--- a/ethereum/anvil_fork
+++ b/ethereum/anvil_fork
@@ -5,11 +5,12 @@ set -euo pipefail
 # This script forks a chain using anvil with the mnemonic that is used in the
 # testing environment.
 
-if [ -z "$1" ]; then
+CHAIN_NAME="${1:-}"
+
+if [ -z "$CHAIN_NAME" ]; then
   echo "Usage: $0 <chain name>" >&2
   exit 1
 fi
 
-CHAIN_NAME="$1"
 
 DOCKER_ARGS="-p 8545:8545" ./foundry anvil --host 0.0.0.0 --base-fee 0 --fork-url $(worm info rpc mainnet $CHAIN_NAME) --mnemonic "myth like bonus scare over problem client lizard pioneer submit female collect"
diff --git a/ethereum/sh/upgrade.sh b/ethereum/sh/upgrade.sh
index 42e8c87b90..947b166181 100755
--- a/ethereum/sh/upgrade.sh
+++ b/ethereum/sh/upgrade.sh
@@ -8,14 +8,28 @@
 
 set -euo pipefail
 
-network=$1
-module=$2
-chain=$3
+network="${1:-}"
+module="${2:-}"
+chain="${3:-}"
+
+if [ -z "$network" ] || [ -z "$module" ] || [ -z "$chain" ]; then
+  echo "Usage: MNEMONIC=... $0 <network> <module> <chain name>" >&2
+  exit 1
+fi
+
+if [ -z "${MNEMONIC:-}" ]; then
+  echo "MNEMONIC unset"
+  exit 1
+fi
 
 secret=$MNEMONIC
 guardian_secret=""
 
 if [ "$network" = testnet ]; then
+  if [ -z "${GUARDIAN_MNEMONIC:-}" ]; then
+    echo "GUARDIAN_MNEMONIC unset"
+    exit 1
+  fi
   guardian_secret=$GUARDIAN_MNEMONIC
 fi
 
@@ -114,4 +128,4 @@ if [ "$network" = testnet ]; then
   worm submit $(worm generate upgrade -c "$chain" -a "$new_implementation" -m "$module" -g "$guardian_secret") -n "$network"
 else
   echo "../scripts/contract-upgrade-governance.sh -c $chain -m $verify_module -a $new_implementation"
-fi
\ No newline at end of file
+fi
diff --git a/ethereum/sh/upgrade_all_testnet.sh b/ethereum/sh/upgrade_all_testnet.sh
index de3c283023..334fcde598 100755
--- a/ethereum/sh/upgrade_all_testnet.sh
+++ b/ethereum/sh/upgrade_all_testnet.sh
@@ -21,7 +21,7 @@ set -uo pipefail
 network=testnet
 
 for module in ${MODULES[@]}; do
-  for chain in ${chains[@]}; do
+  for chain in ${CHAINS[@]}; do
     echo "Upgrading ${chain} ${module} ********************************************************************"
     ./sh/upgrade.sh "$network" "$module" "$chain"
   done