diff --git a/internal/processor/string-create_test.go b/internal/processor/string-create_test.go
index 54e0527..6082229 100644
--- a/internal/processor/string-create_test.go
+++ b/internal/processor/string-create_test.go
@@ -4,6 +4,7 @@ import (
 	"testing"
 	"text/template"
 
+	"github.com/jwetzell/showbridge-go/internal/config"
 	"github.com/jwetzell/showbridge-go/internal/processor"
 )
 
@@ -15,6 +16,39 @@ func (t TestStruct) GetData() string {
 	return t.Data
 }
 
+func TestStringCreateFromRegistry(t *testing.T) {
+	registration, ok := processor.ProcessorRegistry["string.create"]
+	if !ok {
+		t.Fatalf("string.create processor not registered")
+	}
+
+	processorInstance, err := registration.New(config.ProcessorConfig{
+		Type: "string.create",
+		Params: map[string]any{
+			"template": "{{.}}",
+		},
+	})
+	if err != nil {
+		t.Fatalf("failed to create string.create processor: %s", err)
+	}
+
+	if processorInstance.Type() != "string.create" {
+		t.Fatalf("string.create processor has wrong type: %s", processorInstance.Type())
+	}
+
+	payload := "hello"
+	expected := "hello"
+
+	got, err := processorInstance.Process(t.Context(), payload)
+	if err != nil {
+		t.Fatalf("string.create processing failed: %s", err)
+	}
+
+	if got != expected {
+		t.Fatalf("string.create got %+v, expected %+v", got, expected)
+	}
+}
+
 func TestGoodStringCreate(t *testing.T) {
 
 	tests := []struct {
@@ -79,3 +113,75 @@ func TestGoodStringCreate(t *testing.T) {
 		})
 	}
 }
+
+func TestBadStringCreate(t *testing.T) {
+	tests := []struct {
+		name        string
+		params      map[string]any
+		payload     any
+		errorString string
+	}{
+		{
+			name:        "no template param",
+			payload:     "hello",
+			params:      map[string]any{},
+			errorString: "string.create requires a template parameter",
+		},
+		{
+			name:    "non string template",
+			payload: "hello",
+			params: map[string]any{
+				"template": 1,
+			},
+			errorString: "string.create template must be a string",
+		},
+		{
+			name:    "invalid template",
+			payload: "hello",
+			params: map[string]any{
+				"template": "{{.",
+			},
+			errorString: "template: template:1: illegal number syntax: \".\"",
+		},
+		{
+			name:    "bad property in template",
+			payload: "hello",
+			params: map[string]any{
+				"template": "{{.Invalid}}",
+			},
+			errorString: "template: template:1:2: executing \"template\" at <.Invalid>: can't evaluate field Invalid in type string",
+		},
+	}
+
+	for _, test := range tests {
+		t.Run(test.name, func(t *testing.T) {
+
+			registration, ok := processor.ProcessorRegistry["string.create"]
+			if !ok {
+				t.Fatalf("string.create processor not registered")
+			}
+
+			processorInstance, err := registration.New(config.ProcessorConfig{
+				Type:   "string.create",
+				Params: test.params,
+			})
+
+			if err != nil {
+				if test.errorString != err.Error() {
+					t.Fatalf("string.encode got error '%s', expected '%s'", err.Error(), test.errorString)
+				}
+				return
+			}
+
+			got, err := processorInstance.Process(t.Context(), test.payload)
+
+			if err == nil {
+				t.Fatalf("string.encode expected to fail but got payload: %s", got)
+			}
+
+			if err.Error() != test.errorString {
+				t.Fatalf("string.encode got error '%s', expected '%s'", err.Error(), test.errorString)
+			}
+		})
+	}
+}
diff --git a/internal/processor/string-decode_test.go b/internal/processor/string-decode_test.go
index ac80465..b90251e 100644
--- a/internal/processor/string-decode_test.go
+++ b/internal/processor/string-decode_test.go
@@ -3,9 +3,40 @@ package processor_test
 import (
 	"testing"
 
+	"github.com/jwetzell/showbridge-go/internal/config"
 	"github.com/jwetzell/showbridge-go/internal/processor"
 )
 
+func TestStringDecodeFromRegistry(t *testing.T) {
+	registration, ok := processor.ProcessorRegistry["string.decode"]
+	if !ok {
+		t.Fatalf("string.decode processor not registered")
+	}
+
+	processorInstance, err := registration.New(config.ProcessorConfig{
+		Type: "string.decode",
+	})
+	if err != nil {
+		t.Fatalf("failed to create string.decode processor: %s", err)
+	}
+
+	if processorInstance.Type() != "string.decode" {
+		t.Fatalf("string.decode processor has wrong type: %s", processorInstance.Type())
+	}
+
+	payload := []byte{'h', 'e', 'l', 'l', 'o'}
+	expected := "hello"
+
+	got, err := processorInstance.Process(t.Context(), payload)
+	if err != nil {
+		t.Fatalf("string.decode processing failed: %s", err)
+	}
+
+	if got != expected {
+		t.Fatalf("string.decode got %+v, expected %+v", got, expected)
+	}
+}
+
 func TestGoodStringDecode(t *testing.T) {
 	stringDecoder := processor.StringDecode{}
 	tests := []struct {
diff --git a/internal/processor/string-encode_test.go b/internal/processor/string-encode_test.go
index b86ad2d..95c1c9a 100644
--- a/internal/processor/string-encode_test.go
+++ b/internal/processor/string-encode_test.go
@@ -4,9 +4,46 @@ import (
 	"slices"
 	"testing"
 
+	"github.com/jwetzell/showbridge-go/internal/config"
 	"github.com/jwetzell/showbridge-go/internal/processor"
 )
 
+func TestStringEncodeFromRegistry(t *testing.T) {
+	registration, ok := processor.ProcessorRegistry["string.encode"]
+	if !ok {
+		t.Fatalf("string.encode processor not registered")
+	}
+
+	processorInstance, err := registration.New(config.ProcessorConfig{
+		Type: "string.encode",
+	})
+	if err != nil {
+		t.Fatalf("failed to create string.encode processor: %s", err)
+	}
+
+	if processorInstance.Type() != "string.encode" {
+		t.Fatalf("string.encode processor has wrong type: %s", processorInstance.Type())
+	}
+
+	payload := "hello"
+	expected := []byte{'h', 'e', 'l', 'l', 'o'}
+
+	got, err := processorInstance.Process(t.Context(), payload)
+	if err != nil {
+		t.Fatalf("string.encode processing failed: %s", err)
+	}
+
+	gotBytes, ok := got.([]byte)
+
+	if !ok {
+		t.Fatalf("string.encode should return byte slice")
+	}
+
+	if !slices.Equal(gotBytes, expected) {
+		t.Fatalf("string.encode got %+v, expected %+v", got, expected)
+	}
+}
+
 func TestGoodStringEncode(t *testing.T) {
 	stringEncoder := processor.StringEncode{}
 	tests := []struct {