diff --git a/langfuse/api/reference.md b/langfuse/api/reference.md
index 8a8dad23c..ea094fce8 100644
--- a/langfuse/api/reference.md
+++ b/langfuse/api/reference.md
@@ -3743,8 +3743,9 @@ Example: "key1,key2"
 
 **parse_io_as_json:** `typing.Optional[bool]` 
 
-Set to `true` to parse input/output fields as JSON, or `false` to return raw strings.
-Defaults to `false` if not provided.
+**Deprecated.** Setting this to `true` will return a 400 error.
+Input/output fields are always returned as raw strings.
+Remove this parameter or set it to `false`.
     
 </dd>
 </dl>
@@ -7207,6 +7208,14 @@ client.score_v_2.get()
 <dl>
 <dd>
 
+**filter:** `typing.Optional[str]` — A JSON stringified array of filter objects. Each object requires type, column, operator, and value. Supports filtering by score metadata using the stringObject type. Example: [{"type":"stringObject","column":"metadata","key":"user_id","operator":"=","value":"abc123"}]. Supported types: stringObject (metadata key-value filtering), string, number, datetime, stringOptions, arrayOptions. Supported operators for stringObject: =, contains, does not contain, starts with, ends with.
+    
+</dd>
+</dl>
+
+<dl>
+<dd>
+
 **request_options:** `typing.Optional[RequestOptions]` — Request-specific configuration.
     
 </dd>
diff --git a/langfuse/api/resources/observations_v_2/client.py b/langfuse/api/resources/observations_v_2/client.py
index ea9599c69..fc48a6a53 100644
--- a/langfuse/api/resources/observations_v_2/client.py
+++ b/langfuse/api/resources/observations_v_2/client.py
@@ -90,8 +90,9 @@ def get_many(
             Base64-encoded cursor for pagination. Use the cursor from the previous response to get the next page.
 
         parse_io_as_json : typing.Optional[bool]
-            Set to `true` to parse input/output fields as JSON, or `false` to return raw strings.
-            Defaults to `false` if not provided.
+            **Deprecated.** Setting this to `true` will return a 400 error.
+            Input/output fields are always returned as raw strings.
+            Remove this parameter or set it to `false`.
 
         name : typing.Optional[str]
 
@@ -364,8 +365,9 @@ async def get_many(
             Base64-encoded cursor for pagination. Use the cursor from the previous response to get the next page.
 
         parse_io_as_json : typing.Optional[bool]
-            Set to `true` to parse input/output fields as JSON, or `false` to return raw strings.
-            Defaults to `false` if not provided.
+            **Deprecated.** Setting this to `true` will return a 400 error.
+            Input/output fields are always returned as raw strings.
+            Remove this parameter or set it to `false`.
 
         name : typing.Optional[str]
 
diff --git a/langfuse/api/resources/score_v_2/client.py b/langfuse/api/resources/score_v_2/client.py
index 7372a7784..bce290023 100644
--- a/langfuse/api/resources/score_v_2/client.py
+++ b/langfuse/api/resources/score_v_2/client.py
@@ -48,6 +48,7 @@ def get(
         data_type: typing.Optional[ScoreDataType] = None,
         trace_tags: typing.Optional[typing.Union[str, typing.Sequence[str]]] = None,
         fields: typing.Optional[str] = None,
+        filter: typing.Optional[str] = None,
         request_options: typing.Optional[RequestOptions] = None,
     ) -> GetScoresResponse:
         """
@@ -115,6 +116,9 @@ def get(
         fields : typing.Optional[str]
             Comma-separated list of field groups to include in the response. Available field groups: 'score' (core score fields), 'trace' (trace properties: userId, tags, environment). If not specified, both 'score' and 'trace' are returned by default. Example: 'score' to exclude trace data, 'score,trace' to include both. Note: When filtering by trace properties (using userId or traceTags parameters), the 'trace' field group must be included, otherwise a 400 error will be returned.
 
+        filter : typing.Optional[str]
+            A JSON stringified array of filter objects. Each object requires type, column, operator, and value. Supports filtering by score metadata using the stringObject type. Example: [{"type":"stringObject","column":"metadata","key":"user_id","operator":"=","value":"abc123"}]. Supported types: stringObject (metadata key-value filtering), string, number, datetime, stringOptions, arrayOptions. Supported operators for stringObject: =, contains, does not contain, starts with, ends with.
+
         request_options : typing.Optional[RequestOptions]
             Request-specific configuration.
 
@@ -164,6 +168,7 @@ def get(
                 "dataType": data_type,
                 "traceTags": trace_tags,
                 "fields": fields,
+                "filter": filter,
             },
             request_options=request_options,
         )
@@ -286,6 +291,7 @@ async def get(
         data_type: typing.Optional[ScoreDataType] = None,
         trace_tags: typing.Optional[typing.Union[str, typing.Sequence[str]]] = None,
         fields: typing.Optional[str] = None,
+        filter: typing.Optional[str] = None,
         request_options: typing.Optional[RequestOptions] = None,
     ) -> GetScoresResponse:
         """
@@ -353,6 +359,9 @@ async def get(
         fields : typing.Optional[str]
             Comma-separated list of field groups to include in the response. Available field groups: 'score' (core score fields), 'trace' (trace properties: userId, tags, environment). If not specified, both 'score' and 'trace' are returned by default. Example: 'score' to exclude trace data, 'score,trace' to include both. Note: When filtering by trace properties (using userId or traceTags parameters), the 'trace' field group must be included, otherwise a 400 error will be returned.
 
+        filter : typing.Optional[str]
+            A JSON stringified array of filter objects. Each object requires type, column, operator, and value. Supports filtering by score metadata using the stringObject type. Example: [{"type":"stringObject","column":"metadata","key":"user_id","operator":"=","value":"abc123"}]. Supported types: stringObject (metadata key-value filtering), string, number, datetime, stringOptions, arrayOptions. Supported operators for stringObject: =, contains, does not contain, starts with, ends with.
+
         request_options : typing.Optional[RequestOptions]
             Request-specific configuration.
 
@@ -410,6 +419,7 @@ async def main() -> None:
                 "dataType": data_type,
                 "traceTags": trace_tags,
                 "fields": fields,
+                "filter": filter,
             },
             request_options=request_options,
         )