--- title: "langfuse Breaking Changes on PyPI | Since.dev" description: "What each langfuse release removed, renamed or changed: 2,531 breaking changes in 8 versions on PyPI, each with its source." canonical_url: https://since.dev/packages/pypi/langfuse last_updated: 2026-10-30 --- # langfuse breaking changes Every breaking API change we have recorded in langfuse on PyPI: 2,531 breaking changes in 8 versions. Below are its newest 6 versions, removals and renames first, each with its source. Newest change October 30, 2026 ## 5.1.0 34 breaking changes, first published October 30, 2026. - **Removed** `langfuse.api.client.UnstableClient.skills` UnstableClient.skills was removed in langfuse 5.1.0 [pypi.org](https://pypi.org/project/langfuse/5.1.0/) - **Removed** `langfuse.api.unstable.client.AsyncSkillsClient` langfuse.api.unstable.client.AsyncSkillsClient was removed in langfuse 5.1.0 [pypi.org](https://pypi.org/project/langfuse/5.1.0/) - **Removed** `langfuse.api.unstable.client.SkillsClient` langfuse.api.unstable.client.SkillsClient was removed in langfuse 5.1.0 [pypi.org](https://pypi.org/project/langfuse/5.1.0/) - **Removed** `langfuse.api.unstable.CreateSkillVersionRequest` langfuse.api.unstable.CreateSkillVersionRequest was removed in langfuse 5.1.0 [pypi.org](https://pypi.org/project/langfuse/5.1.0/) - **Removed** `langfuse.api.unstable.DeleteSkillVersionResponse` langfuse.api.unstable.DeleteSkillVersionResponse was removed in langfuse 5.1.0 [pypi.org](https://pypi.org/project/langfuse/5.1.0/) - **Removed** `langfuse.api.unstable.SkillFile` langfuse.api.unstable.SkillFile was removed in langfuse 5.1.0 [pypi.org](https://pypi.org/project/langfuse/5.1.0/) - **Removed** `langfuse.api.unstable.SkillFileContent` langfuse.api.unstable.SkillFileContent was removed in langfuse 5.1.0 [pypi.org](https://pypi.org/project/langfuse/5.1.0/) - **Removed** `langfuse.api.unstable.SkillFileContentsResponse` langfuse.api.unstable.SkillFileContentsResponse was removed in langfuse 5.1.0 [pypi.org](https://pypi.org/project/langfuse/5.1.0/) - **Removed** `langfuse.api.unstable.SkillListPagination` langfuse.api.unstable.SkillListPagination was removed in langfuse 5.1.0 [pypi.org](https://pypi.org/project/langfuse/5.1.0/) - **Removed** `langfuse.api.unstable.SkillMeta` langfuse.api.unstable.SkillMeta was removed in langfuse 5.1.0 [pypi.org](https://pypi.org/project/langfuse/5.1.0/) And 24 more in this version. ## 5.0.3 1 breaking change, first published October 20, 2026. - **Signature changed** `langfuse.RunnerContext.run_experiment` Was def run_experiment(self, \*, name: str, run_name: Optional\[str\] = None, description: Optional\[str\] = None, data: Optional\[ExperimentData\] = None, task: TaskFunction, evaluators: List\[EvaluatorFunction\] = \[\], composite_evaluator... [pypi.org](https://pypi.org/project/langfuse/5.0.3/) ## 5.0.1 220 breaking changes, first published October 14, 2026. - **Removed** The callback handler only supports langchain-core 1 or newer. Upgrade LangChain before using this release. [github.com](https://github.com/langfuse/langfuse-python/commit/f890d1f27d1bb3ad13212e2a658e6e75bc98ef82) - **Removed** v5 needs Python 3.11 or later; on Python 3.10, pip install langfuse installs the latest v4 instead. [langfuse.com](https://langfuse.com/docs/observability/sdk/upgrade-path/python-v4-to-v5) - **Removed** Python 3.10 is no longer supported. Upgrade to Python 3.11 or newer before installing this release. [github.com](https://github.com/langfuse/langfuse-python/commit/f890d1f27d1bb3ad13212e2a658e6e75bc98ef82) - **Removed** The OpenAI integration now only works with OpenAI SDK 1.0 or newer. Upgrade the openai package before using this release. [github.com](https://github.com/langfuse/langfuse-python/commit/f890d1f27d1bb3ad13212e2a658e6e75bc98ef82) - **Removed** v5 does not support self-hosted Langfuse v3 or v4 before v4.59.0. Upgrade Langfuse first, or stay on Python SDK v4. [langfuse.com](https://langfuse.com/docs/observability/sdk/upgrade-path/python-v4-to-v5) - **Removed** `_additional_trace_tags` This private batch evaluation option no longer exists. [github.com](https://github.com/langfuse/langfuse-python/commit/f890d1f27d1bb3ad13212e2a658e6e75bc98ef82) - **Removed** `blocked_instrumentation_scopes` blocked_instrumentation_scopes is gone. Use should_export_span instead. [github.com](https://github.com/langfuse/langfuse-python/commit/f890d1f27d1bb3ad13212e2a658e6e75bc98ef82) - **Removed** `delete_dataset_run` This helper was removed because the endpoints it used are no longer served. Read experiment runs with langfuse.api.experiments.list() and list_items(). [github.com](https://github.com/langfuse/langfuse-python/commit/f890d1f27d1bb3ad13212e2a658e6e75bc98ef82) - **Removed** `get_dataset_run` This helper was removed because the endpoints it used are no longer served. Read experiment runs with langfuse.api.experiments.list() and list_items(). [github.com](https://github.com/langfuse/langfuse-python/commit/f890d1f27d1bb3ad13212e2a658e6e75bc98ef82) - **Removed** `get_dataset_runs` This helper was removed because the endpoints it used are no longer served. Read experiment runs with langfuse.api.experiments.list() and list_items(). [github.com](https://github.com/langfuse/langfuse-python/commit/f890d1f27d1bb3ad13212e2a658e6e75bc98ef82) And 210 more in this version. ## 4.18.0 32 breaking changes, first published October 14, 2026. - **Removed** `langfuse.api.evaluation_commons.types.string_object_evaluation_rule_filter.EvaluationRuleStringFilterOperator` langfuse.api.evaluation_commons.types.string_object_evaluation_rule_filter.EvaluationRuleStringFilterOperator was removed in langfuse 4.18.0 [pypi.org](https://pypi.org/project/langfuse/4.18.0/) - **Removed** `langfuse.api.evaluators.types.cursor_meta.UniversalBaseModel` langfuse.api.evaluators.types.cursor_meta.UniversalBaseModel was removed in langfuse 4.18.0 [pypi.org](https://pypi.org/project/langfuse/4.18.0/) - **Removed** `langfuse.api.experiments.types.experiments_response_meta.UniversalBaseModel` langfuse.api.experiments.types.experiments_response_meta.UniversalBaseModel was removed in langfuse 4.18.0 [pypi.org](https://pypi.org/project/langfuse/4.18.0/) - **Removed** `langfuse.api.observations.types.observations_v2meta.UniversalBaseModel` langfuse.api.observations.types.observations_v2meta.UniversalBaseModel was removed in langfuse 4.18.0 [pypi.org](https://pypi.org/project/langfuse/4.18.0/) - **Removed** `langfuse.api.scores_v3.types.get_scores_v3meta.UniversalBaseModel` langfuse.api.scores_v3.types.get_scores_v3meta.UniversalBaseModel was removed in langfuse 4.18.0 [pypi.org](https://pypi.org/project/langfuse/4.18.0/) - **Signature changed** `langfuse.api.BaseScore.metadata` Was metadata: typing.Any; now metadata: typing.Optional\[typing.Dict\[str, typing.Any\]\]. [pypi.org](https://pypi.org/project/langfuse/4.18.0/) - **Signature changed** `langfuse.api.BaseScoreV1.metadata` Was metadata: typing.Any; now metadata: typing.Optional\[typing.Dict\[str, typing.Any\]\]. [pypi.org](https://pypi.org/project/langfuse/4.18.0/) - **Signature changed** `langfuse.api.CursorMeta` Was class CursorMeta(UniversalBaseModel); now class CursorMeta(CursorMetaResponse). [pypi.org](https://pypi.org/project/langfuse/4.18.0/) - **Signature changed** `langfuse.api.Dataset.expected_output_schema` Was expected_output_schema: typing_extensions.Annotated\[typing.Optional\[typing.Any\], FieldMetadata(alias=expectedOutputSchema)\]; now expected_output_schema: typing_extensions.Annotated\[typing.Optional\[typing.Dict\[str, typing.Any\]\]... [pypi.org](https://pypi.org/project/langfuse/4.18.0/) - **Signature changed** `langfuse.api.Dataset.input_schema` Was input_schema: typing_extensions.Annotated\[typing.Optional\[typing.Any\], FieldMetadata(alias=inputSchema)\]; now input_schema: typing_extensions.Annotated\[typing.Optional\[typing.Dict\[str, typing.Any\]\], FieldMetadata(alias=inputSchema)\]. [pypi.org](https://pypi.org/project/langfuse/4.18.0/) And 22 more in this version. ## 4.16.0 1 breaking change, first published September 30, 2026. - **Default changed** The default OpenTelemetry exporter now caps batches at 64 MiB. Code that relied on the previous larger default batch size may see different batching. [github.com](https://github.com/langfuse/langfuse-python/releases/tag/v4.16.0) ## 4.0.0 2,109 breaking changes, first published March 10, 2026. - **Removed** `langfuse.api.AnnotationQueue.Config.allow_population_by_field_name` langfuse.api.AnnotationQueue.Config.allow_population_by_field_name was removed in langfuse 4.0.0 [pypi.org](https://pypi.org/project/langfuse/4.0.0/) - **Removed** `langfuse.api.AnnotationQueue.Config.extra` langfuse.api.AnnotationQueue.Config.extra was removed in langfuse 4.0.0 [pypi.org](https://pypi.org/project/langfuse/4.0.0/) - **Removed** `langfuse.api.AnnotationQueue.Config.frozen` langfuse.api.AnnotationQueue.Config.frozen was removed in langfuse 4.0.0 [pypi.org](https://pypi.org/project/langfuse/4.0.0/) - **Removed** `langfuse.api.AnnotationQueue.Config.json_encoders` langfuse.api.AnnotationQueue.Config.json_encoders was removed in langfuse 4.0.0 [pypi.org](https://pypi.org/project/langfuse/4.0.0/) - **Removed** `langfuse.api.AnnotationQueue.Config.populate_by_name` langfuse.api.AnnotationQueue.Config.populate_by_name was removed in langfuse 4.0.0 [pypi.org](https://pypi.org/project/langfuse/4.0.0/) - **Removed** `langfuse.api.AnnotationQueue.Config.smart_union` langfuse.api.AnnotationQueue.Config.smart_union was removed in langfuse 4.0.0 [pypi.org](https://pypi.org/project/langfuse/4.0.0/) - **Removed** `langfuse.api.AnnotationQueueAssignmentRequest.Config.allow_population_by_field_name` langfuse.api.AnnotationQueueAssignmentRequest.Config.allow_population_by_field_name was removed in langfuse 4.0.0 [pypi.org](https://pypi.org/project/langfuse/4.0.0/) - **Removed** `langfuse.api.AnnotationQueueAssignmentRequest.Config.extra` langfuse.api.AnnotationQueueAssignmentRequest.Config.extra was removed in langfuse 4.0.0 [pypi.org](https://pypi.org/project/langfuse/4.0.0/) - **Removed** `langfuse.api.AnnotationQueueAssignmentRequest.Config.frozen` langfuse.api.AnnotationQueueAssignmentRequest.Config.frozen was removed in langfuse 4.0.0 [pypi.org](https://pypi.org/project/langfuse/4.0.0/) - **Removed** `langfuse.api.AnnotationQueueAssignmentRequest.Config.json_encoders` langfuse.api.AnnotationQueueAssignmentRequest.Config.json_encoders was removed in langfuse 4.0.0 [pypi.org](https://pypi.org/project/langfuse/4.0.0/) And 2,099 more in this version. ## Check your code These are the changes. 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