diff --git a/pkg/plugin/implementation/reqpreprocessor/reqpreprocessor.go b/pkg/plugin/implementation/reqpreprocessor/reqpreprocessor.go
index 7ca2901..72f1a28 100644
--- a/pkg/plugin/implementation/reqpreprocessor/reqpreprocessor.go
+++ b/pkg/plugin/implementation/reqpreprocessor/reqpreprocessor.go
@@ -19,7 +19,7 @@ type Config struct {
 	ContextKeys []string
 }
 
-const contextKey = "context"
+const contextKeyField = "context"
 
 // NewPreProcessor returns a middleware that processes the incoming request,
 // extracts the context field from the body, and adds relevant values (like subscriber ID).
@@ -44,7 +44,7 @@ func NewPreProcessor(cfg *Config) (func(http.Handler) http.Handler, error) {
 			// Extract context from request.
 			reqContext, ok := req["context"].(map[string]interface{})
 			if !ok {
-				http.Error(w, fmt.Sprintf("%s field not found or invalid.", contextKey), http.StatusBadRequest)
+				http.Error(w, fmt.Sprintf("%s field not found or invalid.", contextKeyField), http.StatusBadRequest)
 				return
 			}
 			var subID any