diff --git a/astra/src/main/java/com/slack/astra/writer/SpanFormatter.java b/astra/src/main/java/com/slack/astra/writer/SpanFormatter.java
index d73a519aeb..b2a5c8c2ea 100644
--- a/astra/src/main/java/com/slack/astra/writer/SpanFormatter.java
+++ b/astra/src/main/java/com/slack/astra/writer/SpanFormatter.java
@@ -21,6 +21,7 @@ public class SpanFormatter {
 
   public static final String DEFAULT_LOG_MESSAGE_TYPE = "INFO";
   public static final String DEFAULT_INDEX_NAME = "unknown";
+  public static final int DEPTH_LIMIT = 3;
 
   public static Timestamp parseDate(String dateStr, Schema.SchemaFieldType type) {
     Instant instant;
@@ -148,14 +149,28 @@ public static List<Trace.KeyValue> convertKVtoProto(
   @VisibleForTesting
   public static List<Trace.KeyValue> convertKVtoProtoDefault(
       String key, Object value, Schema.IngestSchema schema) {
+    return convertKVtoProtoDefault(key, value, schema, DEPTH_LIMIT - 1);
+  }
+
+  @VisibleForTesting
+  public static List<Trace.KeyValue> convertKVtoProtoDefault(
+      String key, Object value, Schema.IngestSchema schema, int depthLimit) {
     List<Trace.KeyValue> tags = new ArrayList<>();
     if (value instanceof Map) {
-      // todo - consider adding a depth param to prevent excessively nested fields
+      if (depthLimit <= 0) {
+        // We could encode the value with json instead of toString to make it more friendly to API
+        // consumers.
+        // NB: Using BINARY here to ensure it is not indexed.
+        tags.add(makeTraceKV(key, value.toString(), Schema.SchemaFieldType.BINARY));
+        return tags;
+      }
+
       ((Map<?, ?>) value)
           .forEach(
               (key1, value1) -> {
                 List<Trace.KeyValue> nestedValues =
-                    convertKVtoProtoDefault(String.format("%s.%s", key, key1), value1, schema);
+                    convertKVtoProtoDefault(
+                        String.format("%s.%s", key, key1), value1, schema, depthLimit - 1);
                 tags.addAll(nestedValues);
               });
     } else if (value instanceof String || value instanceof List) {
diff --git a/astra/src/test/java/com/slack/astra/schema/SpanFormatterWithSchemaTest.java b/astra/src/test/java/com/slack/astra/schema/SpanFormatterWithSchemaTest.java
index a5297c7297..0d290cba16 100644
--- a/astra/src/test/java/com/slack/astra/schema/SpanFormatterWithSchemaTest.java
+++ b/astra/src/test/java/com/slack/astra/schema/SpanFormatterWithSchemaTest.java
@@ -35,6 +35,7 @@
 import java.util.HashMap;
 import java.util.List;
 import java.util.Map;
+import java.util.function.Function;
 import java.util.stream.Collectors;
 import org.apache.commons.io.FileUtils;
 import org.apache.lucene.document.Document;
@@ -157,6 +158,53 @@ public void canParseSimpleMapValues() throws Exception {
         .isEqualTo("subsubvalue1");
   }
 
+  @Test
+  @SuppressWarnings("OptionalGetWithoutIsPresent")
+  public void stopsAtDepthN() throws Exception {
+
+    Function<List<String>, Map<String, Object>> nestedMap =
+        (keyPath) -> {
+          Object value = "value";
+          for (String k : keyPath.reversed()) {
+            value = Map.of(k, value);
+          }
+          return (Map<String, Object>) value;
+        };
+    Map<String, Object> head = nestedMap.apply(List.of("a", "b", "c", "d", "e", "f"));
+    List<Trace.KeyValue> list;
+    list = SpanFormatter.convertKVtoProtoDefault("init", head, schema);
+    assertThat(list.size()).isEqualTo(1);
+    assertThat(list.getFirst().getKey()).isEqualTo("init.a.b");
+    assertThat(list.getFirst().getVBinary().toStringUtf8()).isEqualTo("{c={d={e={f=value}}}}");
+
+    list = SpanFormatter.convertKVtoProtoDefault("init", head, schema, 0);
+    assertThat(list.size()).isEqualTo(1);
+    assertThat(list.getFirst().getKey()).isEqualTo("init");
+
+    list = SpanFormatter.convertKVtoProtoDefault("init", head, schema, 1);
+    assertThat(list.size()).isEqualTo(1);
+    assertThat(list.getFirst().getKey()).isEqualTo("init.a");
+
+    list = SpanFormatter.convertKVtoProtoDefault("init", head, schema, 2);
+    assertThat(list.size()).isEqualTo(1);
+    assertThat(list.getFirst().getKey()).isEqualTo("init.a.b");
+
+    list = SpanFormatter.convertKVtoProtoDefault("init", head, schema, 6);
+    assertThat(list.size()).isEqualTo(1);
+    assertThat(list.getFirst().getKey()).isEqualTo("init.a.b.c.d.e.f");
+
+    list =
+        SpanFormatter.convertKVtoProtoDefault("init", nestedMap.apply(List.of("a", "b")), schema);
+    assertThat(list.size()).isEqualTo(1);
+    assertThat(list.getFirst().getKey()).isEqualTo("init.a.b");
+
+    list =
+        SpanFormatter.convertKVtoProtoDefault(
+            "init", nestedMap.apply(List.of("a", "b", "c")), schema);
+    assertThat(list.size()).isEqualTo(1);
+    assertThat(list.getFirst().getKey()).isEqualTo("init.a.b");
+  }
+
   @Test
   public void parseIndexRequestWithNullValues() throws Exception {
     final File schemaFile =