diff --git a/main/src/com/google/refine/expr/EvalError.java b/main/src/com/google/refine/expr/EvalError.java
index 5f4912deb..34682cdfc 100644
--- a/main/src/com/google/refine/expr/EvalError.java
+++ b/main/src/com/google/refine/expr/EvalError.java
@@ -39,6 +39,8 @@ import java.util.Properties;
 import org.json.JSONException;
 import org.json.JSONWriter;
 
+import com.fasterxml.jackson.annotation.JsonProperty;
+
 import com.google.refine.Jsonizable;
 
 /**
@@ -50,6 +52,7 @@ import com.google.refine.Jsonizable;
 public class EvalError implements Serializable, Jsonizable {
     private static final long serialVersionUID = -102681220092874080L;
     
+    @JsonProperty("message")
     final public String message;
     
     public EvalError(String message) {
@@ -75,5 +78,10 @@ public class EvalError implements Serializable, Jsonizable {
         writer.key("message"); writer.value(message);
         writer.endObject();
     }
+    
+    @JsonProperty("type")
+    public String getType() {
+        return "error";
+    }
 
 }
diff --git a/main/src/com/google/refine/model/ReconStats.java b/main/src/com/google/refine/model/ReconStats.java
index a0c3ea6d4..00f555e29 100644
--- a/main/src/com/google/refine/model/ReconStats.java
+++ b/main/src/com/google/refine/model/ReconStats.java
@@ -40,6 +40,8 @@ import org.json.JSONException;
 import org.json.JSONObject;
 import org.json.JSONWriter;
 
+import com.fasterxml.jackson.annotation.JsonProperty;
+
 import com.google.refine.Jsonizable;
 import com.google.refine.expr.ExpressionUtils;
 import com.google.refine.model.Recon.Judgment;
@@ -53,8 +55,11 @@ public class ReconStats implements Jsonizable {
         );
     }
     
+    @JsonProperty("nonBlanks")
     final public int    nonBlanks;
+    @JsonProperty("newTopics")
     final public int    newTopics;
+    @JsonProperty("matchedTopics")
     final public int    matchedTopics;
     
     public ReconStats(int nonBlanks, int newTopics, int matchedTopics) {
diff --git a/main/src/com/google/refine/model/ReconType.java b/main/src/com/google/refine/model/ReconType.java
index 088da69b5..3f172bf28 100644
--- a/main/src/com/google/refine/model/ReconType.java
+++ b/main/src/com/google/refine/model/ReconType.java
@@ -39,6 +39,8 @@ import org.json.JSONException;
 import org.json.JSONObject;
 import org.json.JSONWriter;
 
+import com.fasterxml.jackson.annotation.JsonProperty;
+
 import com.google.refine.Jsonizable;
 
 /**
@@ -47,7 +49,9 @@ import com.google.refine.Jsonizable;
  * store the (expected) types of new columns.
  */
 public class ReconType implements Jsonizable {
+    @JsonProperty("id")
     public String id;
+    @JsonProperty("name")
     public String name;
 
     public ReconType(String id, String name) {
diff --git a/main/src/com/google/refine/util/ParsingUtilities.java b/main/src/com/google/refine/util/ParsingUtilities.java
index 8b51fcc04..e067a26fd 100644
--- a/main/src/com/google/refine/util/ParsingUtilities.java
+++ b/main/src/com/google/refine/util/ParsingUtilities.java
@@ -59,6 +59,9 @@ import org.json.JSONException;
 import org.json.JSONObject;
 import org.json.JSONTokener;
 
+import com.fasterxml.jackson.annotation.JsonAutoDetect.Visibility;
+import com.fasterxml.jackson.annotation.PropertyAccessor;
+import com.fasterxml.jackson.databind.DeserializationFeature;
 import com.fasterxml.jackson.databind.ObjectMapper;
 import com.fasterxml.jackson.databind.ObjectWriter;
 import com.fasterxml.jackson.databind.module.SimpleModule;
@@ -74,6 +77,8 @@ public class ParsingUtilities {
         module.addSerializer(double.class, new SerializationFilters.DoubleSerializer());
         module.addSerializer(OffsetDateTime.class, new SerializationFilters.DateSerializer());
         mapper.registerModule(module);
+        mapper.setVisibility(PropertyAccessor.ALL, Visibility.NONE);
+        mapper.configure(DeserializationFeature.FAIL_ON_UNKNOWN_PROPERTIES, false);
     }
     
     public static final FilterProvider defaultFilters = new SimpleFilterProvider()