diff --git a/services/chat-backend/pyproject.toml b/services/chat-backend/pyproject.toml
index d2eef9d..83e1040 100644
--- a/services/chat-backend/pyproject.toml
+++ b/services/chat-backend/pyproject.toml
@@ -56,4 +56,4 @@ show_missing = true
 default-groups = ["dev"]
 
 [tlm-core]
-version = "v0.0.41"
+version = "v0.0.42"
diff --git a/services/chat-backend/src/routers/chat.py b/services/chat-backend/src/routers/chat.py
index d0cc257..33a12b9 100644
--- a/services/chat-backend/src/routers/chat.py
+++ b/services/chat-backend/src/routers/chat.py
@@ -13,7 +13,7 @@
 )
 from src.services.azure import apply_azure_ad_token
 from src.services.chat_config import get_reference_config
-from src.services.chat_log_filter import filter_log
+from src.schemas.chat.input import ChatLogField
 from src.utils.models import registry as model_registry
 
 
@@ -99,18 +99,23 @@ async def _handle_request(
 
     # TODO:properly handle multiple completions
     # or maybe don't support n > 1 for now
-    model_completion, score = completions[0]
+    model_completion, tlm_score = completions[0]
 
     result = {
         **model_completion.model_dump(),
         "tlm_metadata": {
-            "trustworthiness_score": float(score),
+            "trustworthiness_score": float(tlm_score.trustworthiness_score),
         },
     }
 
-    filtered_log = filter_log(log, input.options.log)
-    if metadata_log := filtered_log.get(str(0), {}):
-        result["tlm_metadata"]["metadata"] = metadata_log
+    # add explanation to the result if specified
+    if ChatLogField.EXPLANATION in input.options.log:
+        result["tlm_metadata"]["log"] = {"explanation": tlm_score.explanation}
+
+    # TODO: these are internal logs, do not expose for now
+    # filtered_log = filter_log(log, input.options.log)
+    # if metadata_log := filtered_log.get(str(0), {}):
+    #     result["tlm_metadata"]["metadata"] = metadata_log
 
     return result
 
diff --git a/services/chat-backend/src/schemas/chat/input.py b/services/chat-backend/src/schemas/chat/input.py
index 9e27dd5..9ec0dd6 100644
--- a/services/chat-backend/src/schemas/chat/input.py
+++ b/services/chat-backend/src/schemas/chat/input.py
@@ -13,6 +13,8 @@
 class ChatLogField(enum.Enum):
     """The fields to log for a chat completion."""
 
+    EXPLANATION = "explanation"
+
     RESULT_COMPLETION = "result_completion"
     RESULT_SCORE = "result_score"