diff --git a/plugin-api/build.gradle b/plugin-api/build.gradle
index 1770de177b6..f0135ec91d1 100644
--- a/plugin-api/build.gradle
+++ b/plugin-api/build.gradle
@@ -70,7 +70,7 @@ Calculated : ${currentHash}
 tasks.register('checkAPIChanges', FileStateChecker) {
   description = "Checks that the API for the Plugin-API project does not change without deliberate thought"
   files = sourceSets.main.allJava.files
-  knownHash = 'lRmKnDTcM8T+0wZqTBQYIK9SLnyxgUNQ9Cue93VMgwE='
+  knownHash = 'w+IKkNGNQSO4AECcQMEeYX0TriGTdBSFSx5e7e10yuk='
 }
 check.dependsOn('checkAPIChanges')
 
diff --git a/plugin-api/src/main/java/org/hyperledger/besu/plugin/data/BlockTraceResult.java b/plugin-api/src/main/java/org/hyperledger/besu/plugin/data/BlockTraceResult.java
index 923788da452..fb86222af0c 100644
--- a/plugin-api/src/main/java/org/hyperledger/besu/plugin/data/BlockTraceResult.java
+++ b/plugin-api/src/main/java/org/hyperledger/besu/plugin/data/BlockTraceResult.java
@@ -100,6 +100,9 @@ public static Builder builder() {
   public static class Builder {
     List<TransactionTraceResult> transactionTraceResults = new ArrayList<>();
 
+    /** Constructs a new builder instance. */
+    private Builder() {}
+
     /**
      * Adds a transaction trace result to the builder.
      *