Address PR comments

zetaclient/chains/evm/observer/observer.go

@@ -338,7 +338,8 @@ func (ob *Observer) WatchGasPrice() {
 // PostGasPrice posts gas price to zetacore
 // TODO(revamp): move to gas price file
 func (ob *Observer) PostGasPrice() error {
-	// issue: https://github.com/zeta-chain/node/issues/1160
+	// TODO: add ctx to `PostGasPrice(ctx) error`
+	//  https://github.com/zeta-chain/node/issues/1160
 	ctx := context.Background()
 
 	// GAS PRICE

zetaclient/chains/evm/signer/outbound_data.go

@@ -56,8 +56,8 @@ func NewOutboundData(
 	logger zerolog.Logger,
 ) (*OutboundData, bool, error) {
 	outboundParams := cctx.GetCurrentOutboundParam()
-	if outboundParams == nil {
-		return nil, false, errors.New("outboundParams is nil")
+	if err := validateParams(outboundParams); err != nil {
+		return nil, false, err
 	}
 
 	// Check if the CCTX has already been processed
@@ -194,3 +194,11 @@ func determineDestination(cctx *types.CrossChainTx, logger zerolog.Logger) (ethc
 
 	return ethcommon.Address{}, nil, true
 }
+
+func validateParams(params *types.OutboundParams) error {
+	if params == nil || params.GasLimit == 0 {
+		return errors.New("outboundParams is empty")
+	}
+
+	return nil
+}

zetaclient/chains/evm/signer/outbound_data_test.go

@@ -132,4 +132,16 @@ func TestNewOutboundData(t *testing.T) {
 		// ASSERT
 		assert.ErrorContains(t, err, "unknown chain")
 	})
+
+	t.Run("no outbound params", func(t *testing.T) {
+		// ARRANGE
+		cctx := getCCTX(t)
+		cctx.OutboundParams = nil
+
+		// ACT
+		_, _, err := newOutbound(cctx)
+
+		// ASSERT
+		assert.ErrorContains(t, err, "outboundParams is empty")
+	})
 }