feat(batch-evaluation)!: evaluate observations via the v2 observations API

.github/workflows/ci.yml

@@ -159,8 +159,6 @@ jobs:
           LANGFUSE_SERVER_SHA="$(git ls-remote https://github.com/langfuse/langfuse.git HEAD | cut -f1)"
           curl -fsSL "https://raw.githubusercontent.com/langfuse/langfuse/${LANGFUSE_SERVER_SHA}/docker-compose.yml" \
             -o ./langfuse-server/docker-compose.yml
-          cp ./.github/langfuse-v4-dual-write.override.yml \
-            ./langfuse-server/docker-compose.override.yml
           echo "${LANGFUSE_SERVER_SHA}"
 
       - name: Run langfuse server

langfuse/_client/attributes.py

@@ -32,8 +32,6 @@ class LangfuseOtelSpanAttributes:
     TRACE_TAGS = "langfuse.trace.tags"
     TRACE_PUBLIC = "langfuse.trace.public"
     TRACE_METADATA = "langfuse.trace.metadata"
-    TRACE_INPUT = "langfuse.trace.input"
-    TRACE_OUTPUT = "langfuse.trace.output"
 
     # Langfuse-observation attributes
     OBSERVATION_TYPE = "langfuse.observation.type"
@@ -76,13 +74,9 @@ class LangfuseOtelSpanAttributes:
 
 def create_trace_attributes(
     *,
-    input: Optional[Any] = None,
-    output: Optional[Any] = None,
     public: Optional[bool] = None,
 ) -> dict:
     attributes = {
-        LangfuseOtelSpanAttributes.TRACE_INPUT: _serialize(input),
-        LangfuseOtelSpanAttributes.TRACE_OUTPUT: _serialize(output),
         LangfuseOtelSpanAttributes.TRACE_PUBLIC: public,
     }
 

langfuse/_client/span.py

@@ -36,7 +36,6 @@
 if TYPE_CHECKING:
     from langfuse._client.client import Langfuse
 
-from typing_extensions import deprecated
 
 from langfuse._client.attributes import (
     LangfuseOtelSpanAttributes,
@@ -226,53 +225,6 @@ def end(self, *, end_time: Optional[int] = None) -> "LangfuseObservationWrapper"
 
         return self
 
-    @deprecated(
-        "Trace-level input/output is deprecated. "
-        "For trace attributes (user_id, session_id, tags, etc.), use propagate_attributes() instead. "
-        "This method will be removed in a future major version."
-    )
-    def set_trace_io(
-        self,
-        *,
-        input: Optional[Any] = None,
-        output: Optional[Any] = None,
-    ) -> "LangfuseObservationWrapper":
-        """Set trace-level input and output for the trace this span belongs to.
-
-        .. deprecated::
-            This is a legacy method for backward compatibility with Langfuse platform
-            features that still rely on trace-level input/output (e.g., legacy LLM-as-a-judge
-            evaluators). It will be removed in a future major version.
-
-            For setting other trace attributes (user_id, session_id, metadata, tags, version),
-            use :func:`langfuse.propagate_attributes` (top-level import) instead.
-
-        Args:
-            input: Input data to associate with the trace.
-            output: Output data to associate with the trace.
-
-        Returns:
-            The span instance for method chaining.
-        """
-        if not self._otel_span.is_recording():
-            return self
-
-        media_processed_input = self._process_media_and_apply_mask(
-            data=input, field="input", span=self._otel_span
-        )
-        media_processed_output = self._process_media_and_apply_mask(
-            data=output, field="output", span=self._otel_span
-        )
-
-        attributes = create_trace_attributes(
-            input=media_processed_input,
-            output=media_processed_output,
-        )
-
-        self._otel_span.set_attributes(attributes)
-
-        return self
-
     def set_trace_as_public(self) -> "LangfuseObservationWrapper":
         """Make this trace publicly accessible via its URL.
 

langfuse/_client/span_exporter.py

@@ -27,7 +27,6 @@
 
 _INPUT_MEDIA_ATTRIBUTE_KEYS = frozenset(
     {
-        LangfuseOtelSpanAttributes.TRACE_INPUT,
         LangfuseOtelSpanAttributes.OBSERVATION_INPUT,
         "ai.prompt.messages",
         "ai.prompt",
@@ -54,7 +53,6 @@
 
 _OUTPUT_MEDIA_ATTRIBUTE_KEYS = frozenset(
     {
-        LangfuseOtelSpanAttributes.TRACE_OUTPUT,
         LangfuseOtelSpanAttributes.OBSERVATION_OUTPUT,
         "ai.response.text",
         "ai.result.text",