MLflow Release Notes

MLflow 3.17.1 is a patch release that contains some minor feature enhancements, bug fixes, and documentation updates.

Features

• [Docs / Evaluation] Support Decision API in make_judge() (#26578, @B-Step62)
• [Evaluation] Add mlflow.genai.databricks.review_queues for managing review queues on Databricks (#26414, @harupy)

Bug fixes

• [Tracing] Fix Claude Code OTel trace rendering in the MLflow UI (#26547, @joshuawong-db)
• [Evaluation] Load latest Databricks scorers from the scheduled-scorers REST config so feedback records the scorer version (#26542, @joshuawong-db)

Small bug fixes and documentation updates

• #26680, @joshuawong-db; #26584, @copilot-swe-agent; #26705, @kriscon-db

Major New Features

MLflow 3.17.0 includes several major features and improvements.

Jev Decisions Across Evaluation, Gateway, and Tracing: Use TypeSafe models in built-in scorers and custom judges with typed Boolean or categorical feedback. (#26100, @B-Step62)

Fine-Grained Permissions for Shared Resources: Control access to contained resource types, including runs, traces, and versions, with wildcard grants and explicit DENY. (#26157, @rrrkharse)

Faster Analytics for Large Trace Datasets: Reduce SQL analytics query overhead with opt-in daily summaries and raw-query fallback. (#25991, @HumairAK)

Clearer Evaluation Results: Associate aggregate logged-model evaluation metrics with the managed dataset that produced them. (#25927, @joshuawong-db)

Assistant Improvements for Shared Servers: Keep saved conversations scoped to the signed-in user and reset the active session when accounts change. (#26009, @kriscon-db)

Database upgrade: SQL-backed servers require a coordinated schema upgrade with all writers stopped and a restorable backup, even when daily rollups remain disabled. Run mlflow db upgrade <database-url> before restarting all replicas on the new MLflow version. Mixed-version rolling upgrades are not supported. Follow the database upgrade instructions.

Other Assorted Features & Improvements:

• [Tracing / UI] Add rich rendering for TypeSafe System One traces (#26276, @B-Step62)
• [Build] Show issue-triage progress in a GitHub issue comment (#26454, @copilot-swe-agent)
• [Docs / Evaluation] Allow custom base_url for direct TypeSafe judges (#26445, @B-Step62)
• [Docs / Gateway] Allow custom typesafe_api_base for TypeSafe Gateway endpoints (#26442, @B-Step62)
• [Evaluation / Tracking] Support name IN (...) filters for evaluation-dataset search (#26374, @HumairAK)
• [Docs / Evaluation / Gateway / UI] Support TypeSafe and OpenRouter Jev judges through Gateway System One (#26243, @joshuawong-db)
• [Build / Docs / Tracing / Tracking] Add @mlflow/typesafe tracing integration for TypeSafe AI (#26342, @B-Step62)
• [Build / Docs] Publish Helm charts after stable release images (#26064, @joshuawong-db)
• [Tracing / UI] Add TraceImage to custom trace views (#26297, @chris-chieu)
• [Tracing] Simplify tracing setup defaults in setup.sh (#26341, @B-Step62)
• [Build / Docs / Tracing / Tracking] Add TypeSafe SDK autologging support (#26129, @B-Step62)
• [Tracing / Tracking] Expose OTLP ingestion metrics for Prometheus (#25192, @ashtarkb)
• [Tracing] Compute LLM trace costs client-side for SageMaker tracking (#26178, @B-Step62)
• [Model Registry / Models] Add uc_model_service UC model-version dependency support (#26140, @TomeHirata)
• [Models] Add DatabricksUCModelService resource type (#26137, @TomeHirata)
• [Docs / Tracing / Tracking] Maintain SQL trace analytics daily rollups (#25489, @NeriCarcasci)
• [Docs / Tracing / Tracking] Serve trace analytics reads from opt-in SQL daily rollups (#25239, @NeriCarcasci)
• [Gateway / UI] Add TypeSafe Jev support to the AI Gateway (#26048, @xq-yin)
• [Tracking] Support order_by in search_prompts() across the client, fluent, and GenAI APIs (#25967, @avanish-garg)
• [Docs / Gateway] Add OpenAI-compatible model discovery to the MLflow Gateway (#25940, @RussellLuo)
• [Gateway] Add Anthropic Messages passthrough to AmazonBedrockProvider (#25863, @rhamzatov)
• [Tracking] Support logged model artifacts in the createPresignedUploadUrl endpoint (#24765, @henishborad)
• [Tracking] Add mlflow.restore_experiment() and mlflow.restore_run() to the fluent API (#25852, @avanish-garg)
• [Build] Configure topology spread constraints in the Helm chart (#25778, @daanknoope)
• [Docs / Tracing] Add source metadata to TypeScript agent traces (#25825, @B-Step62)
• [Model Registry / UI] Add a source logged model link to the model version page (#25727, @rrioh)
• [Build / Docs] charts: Expose Helm liveness/readiness/startup probes as configuration variables (#25560, @creater29)
• [Gateway / UI] Allow administrators to disable AI Gateway with MLFLOW_ENABLE_AI_GATEWAY (#25236, @DaoDaoNoCode)
• [UI] Add dataset ID to UI (#25234, @janald99)
• [Tracing] Add first-class span description support to @mlflow.trace and mlflow.start_span (#25548, @Rohitkanithi)

Bug fixes

• [Evaluation] Use the baseline's magnitude in min_relative_change checks (#26252, @mavericksea-ai)
• [UI] Support wrapped MCP registry server definitions (#25764, @mprahl)
• [Tracing / Tracking] Fix decimal metric sums and reduce SQL trace query and rollup overhead (#26369, @HumairAK)
• [Evaluation] Fix EvaluationDataset hashing for list-valued targets and predictions (#26433, @LE0-Lin)
• [Tracking] Fix MCP server version filters rewriting quoted values (#26423, @Amazinghorseli)
• [Tracing] Use response key for tool_call_response parts in GenAI semconv export (#26360, @Zhuoxi2000)
• [Models] Add MLFLOW_ALLOW_PICKLE_DESERIALIZATION guard to mlflow.paddle flavor (#26428, @aaronteo-db)
• [Tracing] Support copy.deepcopy and pickle on Span, LazySpan, and Trace (#26307, @Rohitkanithi)
• [Tracing / UI] Rename trace assessment filter to feedback (#26415, @B-Step62)
• [Evaluation / Gateway] Confine custom scorer code execution to the job executor (#26225, @kriscon-db)
• [Gateway] Return 422 for an unmatched tool_call_id in GeminiAdapter (#26253, @codechrl)
• [Tracing] Keep tool and agent names on GenAI semconv execute_tool and invoke_agent spans (#26394, @chrikrah)
• [Gateway] Report finish_reason tool_calls for Anthropic and Gemini tool calls (#26390, @r14dd)
• [Tracing / UI] Fix "Copy link to trace" URL dropping the # hash route (#26378, @aaronteo-db)
• [Evaluation] Fix _strip_markdown_code_blocks for single-line and glued closing code fences (#26332, @lets-order-some-fries)
• [Tracking] Fix server_name filters for MCP access endpoints (#26327, @Amazinghorseli)
• [Evaluation] Fix hashing of nested variable-length arrays (#26311, @gohil-gaurav)
• [Tracing] Fix Bedrock autolog crashing stream loops on non-Anthropic invoke_model_with_response_stream chunks and GPT-6 redactedContent reasoning (#26346, @kimnamu)
• [Model Registry] Fix @latest alias not resolving to the highest model version (#26291, @CTWalk)
• [Tracking] Fix MlflowStorage.set_trial_state_values WAITING trial transitions (#25945, @CoralGarden52)
• [Tracking] Keep server-info responsive when shared WSGI thread pool is exhausted (#26267, @sduvvuri1603)
• [Gateway] Honor tool_choice in Gemini and Vertex AI gateway requests (#26300, @Vaishnavi220506)
• [Gateway] Fix parallel tool call indices in Anthropic streaming (#26269, @r14dd)
• [Gateway] Fix parallel tool call indices in Gemini and LiteLLM streaming (#26270, @r14dd)
• [Tracking] Honor MLFLOW_S3_IGNORE_TLS in multipart artifact download (#26004, @Anurag-M1)
• [Tracking] Read load_text and load_dict artifacts as UTF-8 (#26265, @ppcvote)
• [Models] Make schema _merge with AnyType order-independent (#26260, @JoeyTan21)
• [UI] Fix Parallel Coordinates metric label contrast on Compare Runs (#26275, @Taj010)
• [Tracing] Fix llama_index traces during deferred streaming (#26293, @B-Step62)
• [Tracing] End OpenAI autolog stream span with ERROR status when the stream raises mid-iteration (#26305, @iamhuman-cheolheelee)
• [Tracing] Handle OpenAI streams that yield no chunks in autolog (#26283, @iamhuman-cheolheelee)
• [Build / Tracking] Fix psycopg3 packaging in the db extra (#26271, @abligail)
• [Build / Tracking] Add psycopg3 to the db extra for SQLAlchemy 2.1 compatibility (#26239, @kriscon-db)
• [Tracking] Accept lowercase like, ilike and in in search_logged_models filters (#26249, @SajalDevX)
• [Tracing] Support MLFLOW_TRACE_LOCATION in TypeScript tracing and OpenCode (#23772, @B-Step62)
• [Tracing] Fix Windows trace user attribution (#26221, @joshuawong-db)
• [UI] Fix dataset navigation highlighting on detail pages (#26187, @DaoDaoNoCode)
• [Gateway / Tracing / Tracking] Raise invalid-parameter errors for SQLAlchemy experiment ID parsing (#26223, @joshuawong-db)
• [Tracing] Raise helpful AttributeError on Span.get() access (#26165, @Rohitkanithi)
• [Tracing / Tracking] Fix trace.text search missing non-ASCII span content (#26130, @pablo-legeren)
• [Gateway] Group parallel tool call results into one user turn in GeminiAdapter (#26001, @rhamzatov)
• [Tracing] Propagate session metadata to TypeScript UC root spans (#26209, @B-Step62)
• [Tracing] Strip spaces around --trace-ids entries in mlflow traces delete (#26204, @breken-ai)
• [Tracking] Stop a metric filter from shrinking search_logged_models pages (#26057, @lazarevtill)
• [Gateway] Handle mixed text and functionCall parts in GeminiAdapter (#26109, @r14dd)
• [Tracing] Strip spaces around --order-by entries in mlflow traces search (#26192, @breken-ai)
• [Evaluation / Tracking] Fix numeric attribute parsing in SearchUtils (#26180, @B-Step62)
• [Evaluation / Tracing] calculate_trace_filter_correlation binds integer experiment IDs (#26179, @B-Step62)
• [Tracing] Propagate trace context in mistral and groq autologging (#26177, @B-Step62)
• [Tracking] Eagerly load tags, params and metrics in search_logged_models (#25983, @lazarevtill)
• [Gateway] Evaluate a budget window only against the policy version that defined it (#26075, @rhamzatov)
• [Tracing / Tracking] Add trace_id property and fix repr on Trace (#26007, @Rohitkanithi)
• [Evaluation] Fix loading @scorer functions whose signature contains parentheses (#26172, @anishmehta24)
• [Model Registry] Remove stale aliases when deleting model versions (#26173, @copilot-swe-agent)
• [Tracing] Fix span status description when record_exception is given a string (#26171, @anishmehta24)
• [Evaluation] Fix ndcg_at_k document ID collisions (#26041, @kadyrbekovhamit-cyber)
• [Evaluation] Validate deduplication group references in issue discovery (#26082, @vb-dbrks)
• [Model Registry / Tracking] Coerce numeric SQL search filter values for psycopg v3 (#26170, @copilot-swe-agent)
• [Docs / Models] Preserve backward-compatible serialization defaults for Databricks (#25992, @B-Step62)
• [Models] Use cloudpickle for sklearn models nested in SHAP explainers (#26138, @B-Step62)
• [Tracing] Make bundled model cost lookup deterministic (#26154, @copilot-swe-agent)
• [Tracing] Raise helpful TypeError on Span subscript access (#26008, @Rohitkanithi)
• [Model Registry] Validate CreateModelVersion sources against declared resources (#26037, @joshuawong-db)
• [Tracing] Avoid duplicate MlflowLangchainTracer registration in LangGraph lifecycle callbacks (#26136, @AbdulAliMamnun)
• [UI] Fix the MLflow UI hanging forever when navigator.onLine is false (#25961, @nrhys2005)
• [Gateway] Add support for LiteLLM's responses model mode in the catalog sync (#26095, @TomeHirata)
• [Tracking] Fix health probes auth bypass when static prefix applied (#25114, @adrianAzoitei)
• [Scoring] Preserve inherited fields in nested dataclass signatures (#26071, @HaokaiDing)
• [Tracing / UI] Fix duplicate top-level trace chat messages (#26097, @joshuawong-db)
• [Tracking] Fix MSSQL label schema boolean predicate (#26093, @joshuawong-db)
• [Tracing / UI] Fix precision loss for large numeric-string span attributes in trace explorer (#25219, @vpirhach)
• [Tracing / UI] Support OpenInference request and response model-name attributes (#26047, @xq-yin)
• [Prompts] Scope prompt cache entries by registry (#26066, @joshuawong-db)
• [Gateway] Fix gateway request authorization parsing (#25937, @joshuawong-db)
• [Tracking / UI] Treat .ipynb notebooks as text/plain in artifact preview (#25829, @harshal-paltse)
• [UI] Time out the server-info request instead of hanging the UI (#26027, @nrhys2005)
• [Gateway] Preserve the upstream error message in send_stream_request (#26036, @rhamzatov)
• [Tracking] Fix Azure multipart uploads with DefaultAzureCredential (#26031, @joshuawong-db)
• [Tracing] Fix Claude Code usage spans for tool calls (#25931, @joshuawong-db)
• [Models] Suppress import warnings from mlflow.types.responses (#26033, @joshuawong-db)
• [Tracking] Fix NaN metrics matching numeric search filters in SqlAlchemyStore (#25802, @2sumtech)
• [Model Registry / Tracking] Refuse to connect to client-named artifact hosts outside the default artifact root (GHSA-mr9f-fg8qf-4w4j) (#25891, @tanghaoji)
• [Gateway / Tracking] Reject conflicting protobuf field spellings in request bodies (GHSA-3g8m-hm3x-gh2r) (#25869, @tanghaoji)
• [Evaluation / Tracking] Bind trace_ids to the authorized experiment on issues/invoke and genai/evaluate/invoke (#25873, @tanghaoji)
• [Evaluation] Fix positional Series alignment in eval_results_table (#25799, @Pdevadiga45)
• [UI] Filter assessment metrics by logged model (#25928, @joshuawong-db)
• [Tracking] Fix logged model metric order pagination (#25935, @joshuawong-db)
• [Tracking] Reject scheme-less relative workspace default_artifact_root (#25700, @KR-Ravindra)
• [UI] Reduce unsolicited MLflow Assistant response padding (#25925, @joshuawong-db)
• [Evaluation / Tracking] Match third-party scorer modules exactly instead of by package prefix (GHSA-26p8-2jq9-3vq9) (#25906, @tanghaoji)
• [Model Registry / Tracking] Filter nested run.modelVersions GraphQL field by registered-model permission (GHSA-f253-vggg-rwh8) (#25905, @tanghaoji)
• [Tracking] Scope native FastAPI /jobs/search to the caller under basic-auth (GHSA-9pch-m9gq-c25q) (#25899, @tanghaoji)
• [Gateway / Tracking] Gate CreateGatewaySecret on the workspace create grant in basic-auth (#25895, @tanghaoji)
• [Model Registry / Tracking] Authorize CreateModelVersion camelCase runId/modelId aliases in basic-auth (GHSA-442c-p479-46xg) (#25892, @tanghaoji)
• [Evaluation / Tracking] Reject egress-steering kwargs in third-party scorer payloads (GHSA-2wqp-q3c6-ccj5) (#25890, @tanghaoji)
• [Gateway] Handle non-JSON tool message content in the Gemini gateway adapter (#25868, @rhamzatov)
• [Tracking] Use _bulk_upsert in set_logged_model_tags for SQLite, PostgreSQL, and MySQL (#25862, @rautaditya2606)
• [Evaluation / Tracing] Add Databricks tracking URI guardrail to mlflow.genai.review_queues (#25879, @kishor-rkrishnan)
• [Model Registry / Prompts] Reject schemeless path sources for prompt model versions in _create_model_version (#25870, @tanghaoji)
• [Tracing / Tracking] Redact tracking URI credentials in the mlflow-artifacts scheme error (GHSA-c8c4-r4p8-p4m4) (#25874, @tanghaoji)
• [Gateway] Fix Gemini thoughtSignature placement in AI Gateway adapter (#25865, @aytero)
• [Tracing / Tracking] Sanitize CrewAI LLM credentials from mlflow.crewai.autolog spans (GHSA-j7qq-vr8c-xvw3) (#25845, @tanghaoji)
• [Gateway] Post Vertex AI MaaS raw proxy requests to the /endpoints/openapi base URL (#25834, @rhamzatov)
• [Models] Validate pt2 archives when MLFLOW_ALLOW_PICKLE_DESERIALIZATION is disabled (#25849, @tanghaoji)
• [Gateway] Add vertex_anthropic_betas to control anthropic-beta forwarding for Claude on Vertex AI (#25835, @rhamzatov)
• [Gateway / Tracking] Require USE on the gateway secret for issues/invoke (GHSA-2m86-c5q7-rxgr) (#25848, @tanghaoji)
• [Gateway] Forward VertexAIProvider passthrough and proxy routes to its Claude/MaaS delegates (#25833, @rhamzatov)
• [Docs / Gateway] Validate gateway secret api_base to prevent SSRF (GHSA-h7x2-h6g9-p789) (#25761, @tanghaoji)
• [Tracking] Bound _hard_delete_run memory with bulk deletes (#25773, @dyld-w)
• [Tracing] Fix Codex authentication with databricks:// (#25823, @B-Step62)
• [Tracing] Honor CODEX_HOME when locating Codex transcripts (#25822, @B-Step62)
• [Evaluation / Gateway / Tracking] Fix ScorerVersion experiment ID type after REST hydration (#25768, @CoralGarden52)
• [Tracking] Roll back the experiment when trace-location linking fails in create_experiment (#25604, @adamgurary)
• [Gateway] Map top_p to topP in the Bedrock Titan and AI21 completions adapters (#25795, @Yash-Chindam)
• [Tracing / UI] Fix token totals for grouped trace sessions (#25608, @adamgurary)
• [Tracing] Fix strands.autolog crash on foreign OpenTelemetry spans (#25807, @Hasnaathussain)
• [Models / Scoring] Bound apt socket timeouts in generated serving Dockerfiles (#25800, @copilot-swe-agent)
• [Tracing / UI] Fix custom trace views in the session trace drawer (#25779, @joshuawong-db)
• [Tracking] Fail fast in mlflow server when MLFLOW_FLASK_SERVER_SECRET_KEY is unset for basic-auth (#25754, @tanghaoji)
• [Gateway] Stop forwarding client auth headers on passthrough routes (#25129, @uuzzrm)
• [UI] Fix session-level scorer evaluation silently dropping selected sessions (#24937, @demonze)
• [Tracking] Preserve the original exception when cleanup fails in remove_on_error (#25626, @NestDream)
• [Tracing] Enable async trace logging by default for Claude Code (#25541, @mukeshbhandarkar)
• [Evaluation / Tracking] Authorize scorer/invoke and bind traces to the caller's experiment (GHSA-6c27-cp6h-c66m) (#25721, @kriscon-db)
• [Build] Fail the mlflow-skinny/mlflow-tracing build instead of shipping an empty wheel (#25713, @siddharthgaur1)
• [Evaluation] Fix evaluate list input normalization for NumPy targets (#25623, @CoralGarden52)
• [Tracking] Enforce password policy on the basic-auth password-update path (GHSA-v67f-7g57-fjhv) (#25722, @kriscon-db)
• [Gateway] Preserve an unset max_attempts in FallbackConfig.from_proto (#25532, @VenishPaneliya)
• [UI] Fix Assistant Bash execution on Windows selector loops (#25687, @joshuawong-db)
• [UI] Fix MLflow Assistant CLI providers on Windows with >1 server worker (#24418, @joshuawong-db)
• [Scoring] Reject unsupported env_manager values when building a model container (#25514, @alekseevpavel04)
• [Model Registry] Return None for unset deployment_job_state in UC model-version converters (#25690, @kriscon-db)
• [Model Registry] Fix ModelVersion.to_proto dropping deployment_job_state (#25635, @2sumtech)
• [Server-infra] Count fragment selections in GraphQL query-cost limits (#25665, @kriscon-db)
• [Server-infra / Tracking] Require model_id permission for LogMetric/LogBatch metric routing (#25664, @kriscon-db)
• [Tracing / Tracking] Avoid re-serializing unmodified LazySpan JSON on get-trace-artifact. (#24569, @shivamAmrutia)
• [Evaluation / Gateway] Apply Vertex Anthropic request fields in adapter_class so judges work (#25556, @Yash-Chindam)
• [Evaluation] Fix bullet stripping eating leading hyphens in failure labels (#25588, @copilot-swe-agent)
• [Evaluation / Tracking] Release Databricks SDK connections in rest_utils.http_request (#25561, @TimMsnBlueforte)
• [Tracing] Ignore cross-async-context ValueError when detaching a span (#22945, @SahilKumar75)
• [Tracing / UI] Add span link UI to redesigned trace explorer (#25573, @B-Step62)
• [Build / Scoring] Exclude anyio 4.15.0 which breaks server /health (#25559, @joshuawong-db)
• [Prompts / Tracking] Log Catalog Explorer URL in register_prompt (#24778, @adamgurary)

Documentation updates

• [Docs / Tracing] Update bundled mlflow/assistant/skills to latest upstream (#26455, @B-Step62)
• [Docs] Add a Custom Trace Views page to the tracing docs (#26356, @rrioh)
• [Docs] Update Model Registry tutorial for skops serialization (#26287, @copilot-swe-agent)
• [Docs / Evaluation / Gateway] Document TypeSafe judges and System One Gateway usage (#26153, @joshuawong-db)
• [Docs / Tracing / UI] Use hosted MLflow setup wizard in docs and OSS onboarding (#25949, @B-Step62)
• [Docs] Document missing span types WORKFLOW, TASK, GUARDRAIL and EVALUATOR (#25736, @setsaa)
• [Docs / Model Registry / Prompts] Correct register_prompt return type documentation (#25650, @copilot-swe-agent)
• [Build] Nudge Copilot code review to verify when it's cheap (#25586, @copilot-swe-agent)

Small bug fixes and documentation updates

#26464, #26458, @tanghaoji; #26457, #26456, #26419, #26404, #26403, #26401, #26398, #26391, #26389, #26386, #26385, #26384, #26383, #26382, #26381, #26380, #26379, #26372, #26371, #26357, #26354, #26353, #26350, #26349, #26347, #26345, #26343, #26344, #26330, #26329, #26326, #26325, #26324, #26323, #26322, #26318, #26304, #26299, #26296, #26295, #26294, #26286, #26285, #26281, #26280, #26264, #26255, #26196, #26195, #26183, #26169, #26167, #26168, #26155, #26139, #26145, #26135, #26132, #26118, #26113, #26112, #26110, #26107, #26106, #26098, #26094, #26065, #26044, #26038, #26035, #26030, #26028, #26023, #26020, #26018, #26014, #26013, #26010, #25998, #25996, #25995, #25981, #25968, #25947, #25943, #25939, #25932, #25930, #25910, #25907, #25904, #25902, #25901, #25900, #25896, #25893, #25894, #25876, #25875, #25871, #25866, #25864, #25850, #25846, #25836, #25828, #25819, #25815, #25816, #25814, #25813, #25812, #25811, #25810, #25809, #25804, #25801, #25787, #25786, #25782, #25770, #25765, #25763, #25759, #25758, #25757, #25753, #25752, #25738, #25737, #25731, #25729, #25726, #25724, #25725, #25723, #25705, #25691, #25689, #25688, #25678, #25677, #25674, #25673, #25671, #25669, #25668, #25667, #25661, #25658, #25657, #25656, #25655, #25654, #25652, #25651, #25645, #25642, #25633, #25631, #25628, #25625, #25624, #25620, #25622, #25621, #25619, #25617, #25616, #25614, #25611, #25605, #25603, #25602, #25596, #25594, #25595, #25591, #25592, #25590, #25567, @copilot-swe-agent; #26427, #26424, #26242, #26181, #25952, #25719, #25803, @B-Step62; #26429, @aaronteo-db; #26292, #26257, #26246, #25969, #26120, #26102, #26063, #25964, #25584, #25694, #25582, #25580, #25565, @joshuawong-db; #26263, #26068, #25936, @dependabot; #26245, #26244, @anishmehta24; #25979, @jonburdo; #26205, #25993, #25555, #25550, #25293, #25285, #26012, #25686, #25685, #25684, #25557, #25566, @kriscon-db; #25923, @cyficowley; #24761, @Zuhef; #25200, @bardenr; #24680, #25589, #24877, @NeriCarcasci; #23128, #22974, #24760, #24588, @kramaranya; #22568, #22520, @mprahl; #26124, @HumairAK; #26081, @daanknoope; #25569, @IgorShishkin12; #24699, @Andrej730; #25999, @M-Iswarya2; #25960, @TomeHirata; #25903, @harupy; #24999, @kaikaila; #25134, @MarkHe1222; #25717, @acheamponge; #25583, @hpenedones; #25539, @gustaff-weldon; #25644, @adamgurary; #25636, @chenlichao

MLflow 3.17.0 brings typed decisions into evaluation and tracing, finer control over access to shared resources, and faster analytics for large trace datasets. This release also improves evaluation result attribution and saved Assistant conversations on shared servers.

1. Faster LLM-as-a-Judge with Jev, TypeSafe's System One models

Large evaluation runs can become slow and expensive when every yes/no check calls a general-purpose LLM. MLflow now supports TypeSafe's Jev models as judges. For yes/no or finite-category checks, set model="typesafe:/jev-latest" and use the judge in your existing mlflow.genai.evaluate() workflow.

Jev returns a structured decision, which MLflow records as an assessment. The probability or category distribution is saved in assessment metadata, so you can identify close calls when reviewing results. Jev gives teams a faster, lower-cost option for frequent checks; a versioned model ID keeps comparisons consistent across runs.

2. Observability for System One models in MLflow Tracing

A Jev decision can determine what an agent does next. With mlflow.typesafe.autolog(), MLflow traces synchronous and asynchronous System One calls, capturing the state and questions sent to the model, structured answers, latency, errors, and token usage when available.

The trace viewer presents each TypeSafe answer with its selected value and probability details. You can inspect a close decision alongside the question and state that produced it, without digging through the raw response. This makes it easier to understand unexpected agent behavior and compare decisions across runs.

3. Govern Jev model access through MLflow AI Gateway

MLflow AI Gateway now supports TypeSafe System One calls. Create an endpoint for a Jev model, keep the TypeSafe API key on the server, and send structured questions using the endpoint name. You can change the configured Jev model without changing each application that calls it.

Gateway tracks usage, supports budgets, and can fall back to a compatible Jev model from another provider, such as OpenRouter, after upstream errors or rate limits. Each endpoint gives you one place to manage access and monitor use for its API.

4. Fine-Grained Permissions for Shared Resources

Give collaborators access to an experiment without automatically exposing every kind of resource inside it. Role-based access control now covers runs, traces, assessments, logged models, review queues, and model, prompt, scorer, and MCP-server versions. Administrators can configure these permissions in the Admin UI or through the Python client.

The new DENY permission makes exceptions to broader grants explicit. For example, a reviewer can read experiments while being denied access to traces. Permissions for the new resource types use wildcard scope, bounded by access to their parent containers; individual run or trace IDs are not supported as grant patterns. Existing container permissions continue to apply when no grant is set for a contained resource type.

5. Faster Analytics for Large Trace Datasets

Spend less time waiting for trace dashboards as your datasets grow. SQL-backed analytics now reduce query overhead for trace counts, latency, token usage, costs, and assessments. Optional daily rollups reuse precomputed summaries for eligible historical data, while recent data, partial days, and unsupported queries continue through the raw query path. Trace search and retrieval also avoid unnecessary database and serialization work.

Administrators can enable rollups with MLFLOW_SQL_TRACE_ROLLUPS_ENABLED=true after completing the documented database upgrade and maintenance setup. This schema transition requires a coordinated upgrade with writers stopped; mixed-version rolling upgrades are not supported. The database guide includes an optional resumable preparation command for large installations.

6. Clearer Evaluation Results

Evaluation results are easier to connect to the model and dataset that produced them. Evaluating a logged model against a managed dataset now records the dataset name and digest on aggregate metrics. Assessment summaries on a logged model's Traces page also match that model's traces.

The dataset details page displays a copyable dataset ID, so you can move from the UI to the SDK without extracting it from the browser URL.

7. Assistant Improvements for Shared Servers

Saved Assistant conversations are now scoped to the signed-in user. Switching accounts resets the active session and unfinished prompt, so the next person using the same browser starts with their own conversation. Experimental sandbox deployments also align the fallback container's Python and released MLflow versions with the server.

Full Changelog

For a comprehensive list of changes, see the release change log.

MLflow 3.16.1 is a patch release that includes bug fixes and documentation updates.

Breaking changes

[Docs / Tracking] Remove the default basic-auth admin password shipped in basic_auth.ini (GHSA-gq3w-7jj3-x7gr) (#25751, @tanghaoji)

Features

[Evaluation] Add a timeout option to the @scorer decorator (#25720, @smoorjani)

[Evaluation] Propagate scorer version to assessment metadata (#25570, @B-Step62)

[Tracing] Support span links for Unity Catalog traces (#25597, @B-Step62)

Bug fixes

[Tracing] Resolve Unity Catalog trace locations in Databricks Model Serving without local-store validation (#25884, @james-fletcher-db)

[Model Registry] Fix S3 multipart upload encryption arguments (#25772, @james-fletcher-db)

[Tracking / UI] basic-auth: serve the web UI to non-admins under fail-closed authorization (#25672, @mkBGD)

MLflow 3.16.0 includes several major features and improvements

Major New Features

🎨 Custom Trace Views: Design your own trace UI in plain English — describe the view you want and the MLflow Assistant builds it for you, laying out exactly the fields you care about with no config files or custom code. Save, name, and reuse views per experiment so your whole team shares the same lens on your traces.

🔭 Redesigned Trace Experience (now default): The trace explorer has been rebuilt from the ground up and is now the default — tighter row density, cleaner navigation, and a redesigned span-tree view. Reorder columns, add configurable custom columns from any trace tag or metadata field, and find multi-turn conversations inline via session grouping.

🔗 Span Links: Spans rarely stand alone. MLflow 3.16.0 adds first-class span links so relationships between spans — a retrieval step, a tool call, a downstream trace — are captured and navigable. Record links in your SDK and the trace explorer surfaces them in a dedicated Links tab to jump straight to the destination span.

Breaking changes

• [Server-infra / Tracking] basic-auth: enable fail-closed authorization by default (#25308, @PattaraS)
• [Build / Models] Drop cross version testing for pyspark < 3.4.4 (#25098, @harupy)
• [Gateway / Tracing] fix: Serve FastAPI-native routers under --static-prefix (#24511, @SeiichiroYoshioka)

Features

• [Evaluation / Tracing / Tracking] Add mlflow skills agent hints for GenAI anti-patterns (#25496, @james-fletcher-db)
• [Tracing] Add shell-based MLflow Tracing setup wizard (#25441, @B-Step62)
• [Gateway] Support per-user budget policies in the AI Gateway (USER scope + principal) (#24371, @joelrobin18)
• [Tracing / UI] Add trace-table column reordering to V4 traces tab (#25428, @joshuawong-db)
• [Tracing / UI] Add Expectation field to the traces table filter UI (#25460, @creater29)
• [Tracing / UI] Add saved views to MLflow demo (#25392, @joshuawong-db)
• [Tracing / UI] Add configurable custom trace columns (tags + metadata) to Traces V4 (#25427, @joshuawong-db)
• [Tracing / Tracking / UI] Refresh the Traces V4 table: row density, header, and navigation (#25354, @joshuawong-db)
• [Tracing / UI] Mount Traces V4 as the default traces experience (#25424, @joshuawong-db)
• [Tracing / UI] Port redesigned trace explorer (v2) to OSS (#25355, @joshuawong-db)
• [UI] Deprecate the experiment Sessions tab in favor of Traces session grouping (#25350, @joshuawong-db)
• [Evaluation / Tracing] feat(typescript): add logFeedback and typed trace assessments (#25169, @rajudandigam)
• [Tracing] Point coding agents at the MLflow tracing skill on import mlflow (#25247, @harupy)
• [Evaluation / Gateway] Support UC model services in built-in judges (#25246, @TomeHirata)
• [Tracing / UI] Enable shouldEnableModelTraceExplorerCustomTraceView in OSS (#25245, @aaronteo-db)
• [Tracking] jobs: add configurable Huey storage URL for Redis (#22653, @jeevan6996)
• [Tracking] [chart] Add optional External Secrets Operator support (#24523, @habibaikram1)
• [Evaluation] Enrich mlflow scorers list --builtin with the full scorer catalog (#25003, @joshuawong-db)
• [Tracing / UI] feat(ui): display scorer description in tooltip for custom judges (#22043, @adamgurary)
• [UI] Add Image Grid toggle for run parameters (#23705, @jdoughty04)
• [Tracing / Tracking / UI] [Custom View] Enforce saved view limit per experiment (#25064, @tanghaoji)
• [Tracking] [1/6] basic-auth: fail-closed authorization net + coverage guard (#25065, @PattaraS)
• [Build / Scoring] Bump model serving image to Ubuntu 24.04 and Python 3.11 (#25089, @harupy)
• [] Add SpanLink support to TypeScript SDK (#23480, @robinnarsinghranabhat)
• [Docs / Tracking] [Custom View] Increase experiment tag value limit to 20000 (#25062, @aaronteo-db)
• [Tracing / Tracking] feat(ts-sdk): add MLFLOW_TRACKING_AUTH=kubernetes/kubernetes-namespaced support (#24243, @robinnarsinghranabhat)
• [Tracing / UI] [Custom View] Add custom view deletion (#25057, @tanghaoji)
• [Tracing / UI] [Custom View] Support local Assistant providers with structured responses (#25034, @tanghaoji)
• [Tracing / UI] [Custom View] Submit custom view build prompts directly to Assistant (#25026, @aaronteo-db)
• [] Support optimizing chat-type prompts in optimize_prompts (#23488, @gaurav0107)
• [Docs / Tracking] Add --artifact-policy retarget to mlflow db move-resources for repointing experiment artifact roots (#24635, @gauthierpiarrette)
• [] [5 / N] Add custom view tab UI, save/rename, and experiment tag persistence (#24798, @aaronteo-db)
• [Evaluation] Expose generate_rationale_first through make_judge (#25002, @aaronteo-db)
• [Tracing / UI] [4/N] Add client-tool pause/resume for render_custom_view in Assistant (#24796, @aaronteo-db)
• [Tracing] Enable OpenCode tracing plugin to include reasoning/thinking content in the Span (#22997, @robinnarsinghranabhat)
• [UI] feat: enable parent-child run view in GenAI mode (#24790, @pasainatan)
• [Tracing] Add workspace support to Claude Code plugin (#23773, @Gkrumbach07)
• [Evaluation] Add Databricks scorer versioning support (#24940, @nihalmenon)
• [Tracking] Add artifact_path support for logged model artifacts (#23147, @Sanskar121543)
• [Tracing / UI] [3/N] Add custom view persistence model and prompt context builder (#24794, @aaronteo-db)
• [Tracing / UI] [2/N] Add data-source binding and A2UI message/template validator (#24792, @aaronteo-db)
• [Gateway] Add 13 new models to Databricks AI Gateway model catalog (#24893, @TomeHirata)
• [Evaluation / Tracking / UI] Add Assistant analyze action to evaluation runs (#24865, @joshuawong-db)
• [UI] [1/N] Updated A2UI catalog schema and added typed primitives for custom trace views (#24788, @aaronteo-db)

Bug fixes

• [Tracing] Fix host-only Databricks CLI commands in tracing setup (#25529, @B-Step62)
• [Model Registry] [BUGFIX] Preserve empty webhook fields in partial update_webhook calls (#25509, @CoralGarden52)
• [UI] Wrap the traces toolbar so custom-date controls don't overflow off-screen (#25512, @joshuawong-db)
• [Tracing / UI] Fix V4 trace drawer review action (#25510, @joshuawong-db)
• [Tracing / UI] Fix Custom Views in Traces V4 (#25488, @joshuawong-db)
• [Evaluation / Tracking] Fix proto conversion of DatasetRecordSourceType.UNSPECIFIED dataset record sources (#25230, @2sumtech)
• [Tracing / UI] Fix Traces V4 "1 of 0" footer count on exact trace-id search (#25483, @joshuawong-db)
• [Tracing] fix: prevent async trace queue deadlock during flush (#25264, @mukeshbhandarkar)
• [Evaluation] Fix IndexError in merge_records after to_dict/to_df on empty EvaluationDataset (#25498, @TomeHirata)
• [Tracking] Fix integer/varchar type mismatch in WorkspaceAwareSqlAlchemyStore experiment_id filters (#25232, @mayuriphad)
• [Model Registry] [BUGFIX] Preserve status in partial update_webhook calls (#24842, @abligail)
• [Tracking] Fix search_logged_models quoted-value parsing and invalid-operator message (#25398, @VenishPaneliya)
• [Tracing] Keep @mlflow/openai Chat Completion spans open during streaming (#25416, @copilot-swe-agent)
• [Build] Fix the Helm chart ServiceMonitor rendering a null metrics path (#25365, @aqeelat)
• [Scoring] Return 400 instead of 500 for a non-UTF-8 scoring request body (#25173, @tushardev-365)
• [UI] Fix: show assistant floating button on remote servers with MLFLOW_ENABLE_REMOTE_ASSISTANT=true (#25394, @TomeHirata)
• [UI] Include traceId query param in trace navigation links (#25375, @NJAHNAVI2907)
• [Models] Fix pyfunc load crash on ONNX (name, options) provider entries (#25310, @rrioh)
• [Tracking] fix: use chunked I/O in HdfsArtifactRepository to prevent OOM (#21941, @OneSizeFitsQuorum)
• [Build / Tracking] Fix Windows CI failures: drive-letter paths and OS error messages (#25382, @TomeHirata)
• [Models] Fix empty Responses Agent output streams (#25388, @copilot-swe-agent)
• [Prompts] Remove redundant text from GEPA reflective datasets (#25387, @copilot-swe-agent)
• [Evaluation] Fix stale expectations and record counts on dataset export (#25265, @mprahl)
• [Docs] fix: correct max_output_tokens for 10 Databricks-hosted models (#25360, @TomeHirata)
• [Tracing / UI] Normalize span links from OTLP endpoints in the trace explorer (#25319, @khaledsulayman)
• [Tracing] Flush the SpanBatcher from the trace flush paths so UC-table spans are exported (#25260, @alekseevpavel04)
• [UI] Fix autoscale layout state in metric charts (#25314, @PrithviBadiga)
• [UI] Preserve chart section when switching chart type in RunsChartsConfigureModal (#25283, @DaoDaoNoCode)
• [Scoring / Tracking] Fix scorer experiment_id VARCHAR binds on PostgreSQL + psycopg v3 (#25315, @rexminnis)
• [Gateway] Fix streaming passthrough skipping fallback (#25268, @TomeHirata)
• [Evaluation] Propagate eval_retry_context flags into the scorer thread pool (#25318, @joshuawong-db)
• [] feat: add rate limiting and retry support to automatic evaluation path (#24702, @rahul-oss-sap)
• [UI] fix: Ensure consistent ordering of runs for charts (#25019, @pasainatan)
• [Tracing] Fix basic auth overriding Kubernetes auth in Python SDK (#25131, @karimitanii)
• [Tracking] Ignore S3 directory markers in artifact listing (#23250, @Vinno97)
• [Tracking] [8/8] basic-auth: gate native FastAPI job routes on per-job ownership (#25102, @PattaraS)
• [Gateway / Tracking] [7/8] basic-auth: fail-closed enforcement for native FastAPI routes (#25101, @PattaraS)
• [Evaluation / Tracking] [6/6] basic-auth: gate presigned/invoke/demo/metric-twin; empty the debt list (#25071, @PattaraS)
• [Gateway] basic-auth: redact gateway secrets-config passphrase signal from non-admins (#25298, @PattaraS)
• [UI] Fix stale deps and example in the Optimize Prompt modal (#25143, @PattaraS)
• [Gateway / Tracking] [5/6] basic-auth: gate gateway guardrail/budget/config/discovery + filter list endpoints (#25070, @PattaraS)
• [Tracing / Tracking] Fix $0.00 cost panel for bare Databricks serving-endpoint model names (#24620, @adamgurary)
• [Tracing / Tracking] Read top-level cache_read/creation token counts in openai autolog (#24618, @adamgurary)
• [UI] [MLflow Assistant] Fix trace drawer closing when opening the Assistant provider picker (#25255, @aaronteo-db)
• [] [Security] Deny Assistant Read tool file access when no project directory is configured (#24513, @LiteshGhute)
• [Tracking] Skip entry_point.getLogger() when unavailable in dynamic token config provider (#25207, @serena-ruan)
• [UI] Fix visibility control bug for Evaluation Runs in Gen AI mode (#25094, @pasainatan)
• [Tracking] [4/6] basic-auth: gate job routes on per-job ownership (#25069, @PattaraS)
• [Tracing / Tracking] Offload log_spans() from the async event loop (#25185, @HumairAK)
• [Evaluation / Tracing / Tracking] Fix late-binding closure in configure_autologging_for_evaluation configuring the wrong flavor (#25135, @Koustav-github)
• [Evaluation / Tracking] [3/6] basic-auth: gate issue routes on experiment permission (#25067, @PattaraS)
• [Models] Parse schema datetimes as nanoseconds under pandas 3 (#25119, @harupy)
• [Models] Bound pandas in logged requirements for prophet <1.2.2 (#25118, @harupy)
• [Evaluation / Tracking] [2/6] basic-auth: gate evaluation dataset routes on experiment permission (#25066, @PattaraS)
• [Tracking] [1/6] basic-auth: fail-closed authorization net + coverage guard (#25065, @PattaraS)
• [Tracing / UI] Add copy button for markdown-rendered span values in trace explorer (#24619, @adamgurary)
• [UI] Link evaluation datasets from the run overview dataset drawer (#25061, @PattaraS)
• [Tracing] Map OpenInference prompt-cache token counts in OpenInferenceTranslator (#25039, @felix-xsenda)
• [Tracking] Prevent object-store artifact deletion from removing sibling paths (#25024, @yangbaechu)
• [Docs / Tracing] Honor explicit set_outputs() inside the @mlflow.trace decorator (#24624, @adamgurary)
• [Tracking] [tracking] Fix system metrics resume step without metric history mate… (#23401, @iis-MarkKuang)
• [] fix(gateway): handle missing finish_reason in openai_compatible streaming (#24111, @lavkeshdwivedi)
• [Tracking] fix: Stop SearchUtils._get_value from silently dropping dataset IN clause values (#25045, @kaikaila)
• [Tracing] Surface trace-export auth failures at ERROR instead of silently dropping traces (#24847, @adamgurary)
• [Models] Fix PyFunc artifact path collisions (#24681, @yangbaechu)
• [Build] Bump Docker base image from python:3.10-slim-bullseye to python:3.11-slim-trixie (#24961, @mille-printemps)
• [Models] Fix remaining torch_dtype deprecation warnings on load and save paths (#25017, @rrioh)
• [Tracking] Bound log_batch duplicate-metric recovery in SqlAlchemyStore by batch size (#24683, @jayceguo)
• [] Fix pydantic-ai-slim version detection in autologging (#24959, @jiahao6635)
• [Gateway] fix(gateway): preserve provider usage extras (#25010, @uuzzrm)
• [Tracking] fix(langchain): elevate secondary autolog exception handlers to logger.warning (#22040, @adamgurary)
• [UI] fix(ui): Batch run fetching in CompareRunPage to avoid one request per run (#24894, @daniellok-db)
• [Tracing / Tracking] perf(tracing): index trace archival candidate ordering (#24976, @medisean)
• [Gateway] Preserve provider usage extras in OpenAI-compatible gateway (#25000, @uuzzrm)
• [Models] Fix Windows separators in pyfunc artifact paths (#24432, @evanwrm)
• [Tracking] Fix cross-batch deadlock in concurrent log_batch latest_metrics writes (#24941, @Michael97-li)
• [Tracking] Avoid re-enabling externally-disabled loggers in _configure_mlflow_loggers (#24957, @aaronteo-db)
• [Evaluation] Preserve schema maps when enforcing strict JSON schemas (#24193, @sairavuri-sudo)
• [Tracing] Fix flaky test_search_traces_yields_expected_dataframe_contents by flushing before snapshotting (#24996, @harupy)
• [Gateway] Handle zstd-compressed request bodies on the AI Gateway (#24784, @midhunsomu)
• [Tracing / Tracking] Surface Anthropic prompt-cache token counts in mlflow.pydantic_ai.autolog (#23052, @JasonPan)
• [Tracing] Resolve UC path from active experiment when using get_trace with a plain ID (#24700, @aishdbx)
• [Tracing] Validate trace exists in link_prompts_to_trace (fixes #24067) (#24303, @zibranxo)
• [UI] Hide redundant metric names in chart cards (#23212, @xianjianlf2)
• [Gateway] Fix Bedrock gateway grouping of parallel tool results (#24309, @shivamAmrutia)
• [Tracing / Tracking] fix: use response model name for openai chat (#22325, @hansen-young)
• [Gateway] Reject unspecified linkage_type in gateway model configs instead of returning 500 (#24664, @KunalBharadwaj)
• [Docs / Evaluation / Tracing] Fix: Add trace completion buffer to prevent online evaluator from skipping long-running traces (#22006, @amitmodi)
• [Models] Fix torch_dtype deprecation warning on transformers model load (#24929, @serena-ruan)
• [Tracing] Fix basic-auth after-request handler registration (#24322, @sun-andsky)
• [Gateway] Support Vertex AI eu/us multi-region endpoints in gateway provider (#24932, @aaronteo-db)
• [UI] Allow valid Kubernetes workspace names with consecutive hyphens (#24229, @divya0709)
• [Models / Tracking] Fix model-metric-dataset association broken by stale cached ActiveRun outputs (#21855, @daniellok-db)
• [Tracing] Capture Bedrock prompt caching token fields and normalize input tokens to include them (#24899, @gauthierpiarrette)
• [Tracking] Pre-import databricks.sdk in Databricks to avoid telemetry deadlock (#24841, @aaronteo-db)
• [Tracing] Support haystack 3.x in haystack autologging (#24744, @harupy)
• [Tracing] Honor UC-backed trace storage in Databricks model serving (#24806, @james-fletcher-db)
• [Tracking] Do not hard-fail is_flavor_supported_for_associated_package_versions when flavor module is not installed (#24846, @adamgurary)
• [UI] fix(ui): Fix Chart view unresponsiveness via virtualization in RunsChartsDraggableCardsGridSection (#24012) (#24424, @Alwaysgaurav1)
• [] Fix claude_code provider exceeding Windows cmd.exe command-line limit (#24440, @joshuawong-db)
• [UI] Fix RestoreRunModal to show actual error instead of hardcoded message (#24731, @mihir2921)
• [UI] Fix DeleteRunModal to show actual error instead of hardcoded message (#24730, @mihir2921)
• [UI] [UI] Show error notification when permission-denied for USER role actions (#24722, @mihir2921)
• [Build / Models] Add support for pandas 3.x (#23719, @twanahc)
• [Model Registry] Fix model version string to int cast in registry stores (#24565, @qubeena07)

Documentation updates

• [Docs] Fix environment variable expansion in docker/README.md (#25474, @CoralGarden52)
• [Build] Use Chart.appVersion for the Helm example image (#25458, @CoralGarden52)
• [Docs / Tracing] docs: add TypeScript examples to Kubernetes auth page (#25083, @robinnarsinghranabhat)
• [Docs] Clarify trace-data scope in detect-issues.mdx (#25386, @copilot-swe-agent)
• [Docs] Add Red Hat OpenShift AI to hosting options (#25151, @B-Step62)
• [Docs / Tracing] Honor explicit set_outputs() inside the @mlflow.trace decorator (#24624, @adamgurary)
• [Docs / Tracing] docs: clarify Databricks profile, LangGraph autolog, runs-vs-traces, span attributes (#24954, @adamgurary)
• [Docs / Tracing] docs: warn that delete_traces() does not support Databricks Unity Catalog traces (#24647, @adamgurary)
• [Docs / Gateway] Clarify LiteLLM is an optional extension in AI Gateway docs (#24787, @TomeHirata)

Small bug fixes and documentation updates

#25558, #25553, #25392, #25421, #25407, #24828, #25295, #25249, #25055, #24827, @joshuawong-db; #25547, #25127, #24884, #25501, #24714, #24913, #24879, @B-Step62; #25544, #25542, #25540, #25538, #25537, #25534, #25531, #25530, #25506, #25466, #25436, #25408, #25405, #25390, #25320, #25256, #25023, #25014, #24993, #24992, #24988, #24986, #24955, #24872, #24855, #24856, @copilot-swe-agent; #25545, #25502, #25486, #25485, #25482, #25481, #25478, #25475, #25468, #25467, #25464, #25462, #25461, #25465, #25457, #25456, #25452, #25450, #25447, #25446, #25443, #25437, #25430, #25432, #25423, #25429, #25409, #25420, #25417, #25419, #25401, #25404, #25402, #25396, #25393, #25368, #25358, #25346, #25344, #25343, #25342, #25341, #25339, #25338, #25337, #25335, #25334, #25325, #25316, #25312, #25277, #25276, #25252, #25165, #25163, #25162, #25161, #25160, #25159, #25158, #25156, #25154, #25153, #25152, #25144, #25142, #25124, #25122, #25117, #25109, #25110, #25106, #25103, #25100, #25099, #25096, #25090, #25092, #25091, #25088, #25048, #25047, #25042, #25041, #25037, #25030, #25032, #25031, #25029, #25022, #24996, #24991, #24990, #24987, #24982, #24980, #24977, #24978, #24975, #24974, #24973, #24972, #24971, #24970, #24968, #24966, #24965, #24910, #24908, #24922, #24911, #24909, #24901, #24866, #24874, #24853, #24840, #24839, #24834, #24791, #24751, #24770, @harupy; #25533, #25528, #25305, #25304, #25302, #25296, #25222, @kriscon-db; #25412, #25309, @IgorShishkin12; #25520, #25519, #25015, #24945, #24943, #24944, #24902, #24904, #24905, #24903, @dependabot; #25081, #24880, #24802, @mprahl; #25505, #25500, #25480, #25379, #25360, #25351, #24754, @TomeHirata; #25477, #25459, @CoralGarden52; #25180, @miyakido; #25369, @d0w; #25400, @ArrayPD; #25391, #25329, #25104, @tanghaoji; #25374, @brandonhawi; #24276, #24222, @khaledsulayman; #25272, @kaikaila; #25300, #25097, #25046, #24838, @PattaraS; #24998, @juliafmorgado; #25251, #25212, #25211, #25186, #25060, #25059, #25028, #25025, @aaronteo-db; #25202, @aravgarg28; #22653, #jeevan6996; #25164, @jaceklaskowski; #24925, @darkdi; #25040, @rrioh; #24914, @smoorjani; #24892, @codechrl; #24927, @serena-ruan; #24323, #24678, @NeriCarcasci; #24516, @gauthierpiarrette; #24732, @mihir2921; #24779, @daniellok-db

MLflow 3.16.0 puts you in control of how you observe your GenAI apps. The headline: build your own trace UI just by describing it — the MLflow Assistant turns a plain-English prompt into a custom, reusable trace view. On top of that, this release ships a fully redesigned trace explorer as the default experience and first-class span links for connecting related spans across traces. Here's what's new.

Custom Trace Views

Every team inspects traces differently — so why settle for one fixed layout? In 3.16.0, you can design your own trace UI in plain English. Describe the view you want, and the MLflow Assistant builds it for you: the fields you care about, laid out the way you think about them. It's the power of an LLM and MLflow working together — no config files, no custom code, just a prompt.

Found a layout that clicks? Save it, name it, and reuse it. Views persist per experiment, so your whole team can share the same lens on your traces. Create as many as you need, rename them as your workflow evolves, and delete the ones you've outgrown. Whatever mental model you have for your agent, you can now make the UI match it.

A Redesigned Trace Experience

The trace explorer has been rebuilt from the ground up and is now the default traces experience. The new Traces table brings tighter row density, a cleaner header, and smoother navigation, alongside a redesigned span-tree explorer. Reorder columns to put what matters first, and add configurable custom columns backed by any trace tag or metadata field — so the details you care about are always one glance away.

Sessions are now folded directly into the traces view via session grouping, so multi-turn conversations live right alongside the rest of your traces.

Span Links

Spans rarely stand alone — a retrieval step, a tool call, or a downstream trace is often related to the span you're looking at. MLflow 3.16.0 adds first-class span links so those relationships are captured and navigable. Record links between spans in your SDK, and the trace explorer surfaces them in a dedicated Links tab — click through to jump straight to the destination span.

Full Changelog

For a comprehensive list of changes, see the release change log.

MLflow 3.15.2 is a patch release that includes several major features and improvements.

Features

• [Evaluation] Support immutable evaluation dataset versions (#24845, @danielseong1)
• [Evaluation] Add scorer_ensemble primitive for combining scorer results (#24749, @alkispoly-db)

Bug fixes

• [Evaluation] Preserve base judge invocation flow in MemAlign aligned judges (#24883, @veronicalyu320)
• [Tracking] Pre-import databricks.sdk in Databricks to avoid telemetry deadlock (#24841, @aaronteo-db)
• [Build / Tracking] Align runs.status constraint metadata (#24890, @joshuawong-db)

MLflow 3.15.2 is a patch release that includes several major features and improvements.

Features

• [Evaluation] Support immutable evaluation dataset versions (#24845, @danielseong1)
• [Evaluation] Add scorer_ensemble primitive for combining scorer results (#24749, @alkispoly-db)

Bug fixes

• [Evaluation] Preserve base judge invocation flow in MemAlign aligned judges (#24883, @veronicalyu320)
• [Tracking] Pre-import databricks.sdk in Databricks to avoid telemetry deadlock (#24841, @aaronteo-db)
• [Build / Tracking] Align runs.status constraint metadata (#24890, @joshuawong-db)

For a comprehensive list of changes, see the release change log, and check out the latest documentation on mlflow.org.

MLflow 3.15.1 is a patch release that includes bug fixes and documentation updates.

Bug fixes:

• [Model Registry] Skip env_pack on ARM client images (#24762, @qyc)
• [Scoring / Tracking] Harden version parsing against missing/non-PEP440 versions on Databricks Serverless (#24799, @PattaraS)

Documentation updates:

• [Docs] Clarify scorer versioning documentation (#24769, @nihalmenon)

For a comprehensive list of changes, see the release change log, and check out the latest documentation on mlflow.org.

MLflow 3.15.0 includes several major features and improvements

Major New Features

🧩 MCP Registry: A centralized catalog for registering, versioning, and sharing Model Context Protocol servers — with semantic-versioned configs, promotable aliases, tags, auto-discovered tools, and ready-made connection instructions for Claude Code and .mcp.json. Manage it from the UI, REST API, or Python!

🤖 MLflow Assistant enhancements: The in-app AI assistant now supports multiple LLM providers (Claude Code, Codex, and OpenAI-compatible/Gateway endpoints) chosen from a single settings page, displays live per-session token usage and estimated cost in the composer, and is easier to set up — mlflow agent setup can enable it in one prompt, with API keys stored securely in the Gateway's LLM Connections.

🗂️ Sharable table views: Save named views of the Runs table — capturing columns, order, widths, filters, and sort — and share them by URL.

⚡ Proxy-less artifact upload/download via presigned URLs: Large artifact transfers can now bypass the tracking server and talk directly to cloud storage (e.g. S3) through presigned URLs, cutting server load and timeouts on big files. We fall back to proxied transfer automatically for backward compatibility.

🖼️ Multi-modal attachments in LLM judges: {{ trace }} judges created with make_judge() can now see images captured in trace spans via a new get_span_image tool, which fetches attachments as base64 data URLs and passes them to multimodal models (Anthropic, Gemini, and OpenAI-compatible via litellm) — enabling evaluation of vision tasks, screenshots, and other visual content.

Other Assorted Features & Improvements:

• [Tracing / Tracking] Add Pydantic AI 2.x autologging support (#24721, @B-Step62)
• [Tracing / UI] [3/3] Add action recommendation for low-value issue detection result (#24580, @B-Step62)
• [Gateway] Support per-endpoint budget policies in the AI Gateway (#24370, @joelrobin18)
• [Evaluation / Gateway] Add sap-ai-core:/ provider for SAP AI Core Orchestration v2 with extra_headers support (#24356, @shivamxtech)
• [Model Registry] [Model Registry] Migrate UC model artifact download to native temp-creds (#24576, @AknA13)
• [Gateway / Tracing / UI] [2/3] Simplify issue detection start modal (#24579, @B-Step62)
• [Tracing / UI] [1/3] Run issue detection in the background (#24578, @B-Step62)
• [Tracing] [BUG] Fix otel parent context propagation (#24444, @iyashk)
• [Model Registry] [Model Registry] Gate UC model-registry client on native /api/2.1 endpoints (#24517, @AknA13)
• [Docs / Tracking] Enable artifacts-only mode with workspaces (#24452, @kramaranya)
• [Tracing / UI] Stop eagerly prefetching full neighboring traces in tracing UI (#24411, @DaoDaoNoCode)
• [Docs / Gateway] Authenticate OpenAI-protocol coding agents through the RBAC gateway (#24294, @joshuawong-db)
• [Tracing] feat: add search traces to typescript sdk (#23660, @WUMIKE233)
• [Prompts / UI] Add per-tool cards with a Monaco JSON editor and Format action to the Playground (#24129, @tanghaoji)
• [Prompts / UI] Redesign Playground Tools settings with an Add-tools entry flow (#24102, @tanghaoji)
• [] feat: add Cursor model catalog with Auto and Composer 2.5 pricing (#24078, @TomeHirata)
• [Tracing / Tracking] Support numeric assessment trace filters (#23948, @tanghaoji)

Bug fixes:

• [Tracing] Compute mlflow.llm.cost for Claude Code plugin traces on Databricks (#24416, @harupy)
• [UI] Fix artifact direct download capability checks in UI (#24748, @B-Step62)
• [Tracing / UI] Refresh traces saved-view on load across multiple windows (#24746, @joshuawong-db)
• [UI] Fix UnauthorizedError constructor message (#24729, @mihir2921)
• [UI] Fall back to nested spans for Chat Sessions turn content (#24703, @MannXo)
• [Tracing / Tracking] Fix experiment GC cascades for traces and logged models (#24351, @copilot-swe-agent)
• [Tracking] Fix workspace-enabled tracking store crash-loop when the default experiment is renamed (#24598, @daniellok-db)
• [Tracking] Fix Kubernetes auth token extraction for kubernetes-client 36+ (#24687, @HumairAK)
• [UI] Refresh Assistant config when leaving settings so the provider indicator isn't stale (#24704, @joshuawong-db)
• [Build] Fix imagePullSecrets for garbage collection CronJob (#24626, @nightcityblade)
• [UI] Lift Assistant floating button above bottom-pinned action bars (#24606, @joshuawong-db)
• [Evaluation / Tracing] Fix issue detection structured output schema (#24674, @B-Step62)
• [Models] Add MLFLOW_ALLOW_PICKLE_DESERIALIZATION guard to mlflow.statsmodels flavor (#24686, @B-Step62)
• [Tracking] Preserve static prefixes in notebook trace renderer URL (#24682, @mprahl)
• [UI] Fix blank and fields in run detail sidebar (#24634, @aishdbx)
• [Models / Scoring] Normalize reasoning content parts for ChatAgentMessage in parse_message (#24642, @iyashk)
• [UI] Fix Evaluation Runs Actions dropdown remaining clickable when no runs are selected (#24676, @daniellok-db)
• [UI] Surface truncated assistant streams as errors instead of a silent done (#24603, @joshuawong-db)
• [Tracking] Honor experiment grants on --artifacts-only servers when workspaces disabled (#24585, @PattaraS)
• [Tracking / UI] Bound get-history-bulk-interval memory by sampling metric history by row (#24305, @Mytolo)
• [Tracking] [BUG] Enforce artifact authorization on presigned download route in basic-auth (#24571, @iyashk)
• [Evaluation] Preserve explicit expectations in mlflow.genai.evaluate (#24561, @yangbaechu)
• [Gateway / UI] Support Portkey routing configuration in the AI Gateway (#24398, @rs-03)
• [UI] Show input modal submission errors inline instead of a transient toast in GenericInputModal (#23918, @Vedant-Agarwal)
• [Evaluation / Tracking] Enforce experiment permission on online scoring config endpoints (#24562, @aaronteo-db)
• [Tracing / Tracking] Propagate contextvars into trace read thread pool workers (#24456, @iyashk)
• [] Fix Windows path handling in artifact downloads (#20225, @acepace)
• [UI] Fix sidebar navigation and workflow type not updating on URL navigation or browser Back/Forward (#22116, @DaoDaoNoCode)
• [Gateway] Don't send stream_options from the Assistant to the gateway (#24552, @joshuawong-db)
• [Evaluation] Fix MemAlign guideline distillation against Databricks structured-output models (#24547, @veronicalyu320)
• [UI] fix: sort tags alphabetically in runs tag multiselect dropdown (#24134, @mysticalayushi)
• [Tracing] Fix LLM cost on autologged ChatDatabricks traces by preferring ls_provider (#24185, @james-fletcher-db)
• [Tracking] Fix pytorch pt2 export for batch-size-1 input_example (use Dim.AUTO) (#24494, @B-Step62)
• [Tracing / Tracking] Fix double-counted trace token usage for rollup parent spans in SqlAlchemyStore.log_spans (#24339, @gauthierpiarrette)
• [Tracking] Fix MlflowSparkStudy pruner and direction handling (#24425, @hellocybernetics)
• [Gateway / Tracing / UI] Fix gateway Try-in-Browser traces rendering as raw kvlist data in the UI (#24400, @joelrobin18)
• [UI] Fix role modal resource pickers failing with FEATURE_DISABLED when workspaces are disabled (#24441, @joelrobin18)
• [Model Registry] [Model Registry] Restore oneof on TemporaryCredentials.credentials (#24489, @AknA13)
• [UI] [fix] Fix runs-table column reordering before pinned anchors (#24465, @joshuawong-db)
• [UI] Fix admin permission grants failing with FEATURE_DISABLED when workspaces are disabled (#24383, @joelrobin18)
• [UI] Fix Columns dropdown anchoring on the runs table (#24419, @joshuawong-db)
• [UI] Fix artifact viewer crash on text files with many lines (#23899, @jayceguo)
• [Tracing] Fix async trace export dropping workspace context (#24093) (#24275, @vatsalyd)
• [Tracing] fix: store OpenAI agent Generation span attributes under correct SpanAttributeKey constants (#24290, @RudraDudhat2509)
• [Tracing / Tracking] Fix Postgres deadlock between start_trace() and log_spans() on trace metadata (#24338, @joshuawong-db)
• [Tracing / Tracking] Avoid eager span deserialization for TRACKING_STORE trace reads. (#24331, @shivamAmrutia)
• [Gateway] Resolve workspace context before running FastAPI auth validators (#24368, @joelrobin18)
• [Tracing] Fix RecursionError corrupting deeply nested traces (#24362, @joshuawong-db)
• [Evaluation / Tracing] Fix genai.evaluate crash when a cloned trace is unavailable (#24357, @joshuawong-db)
• [Scoring] Handle uncut {major}.x minor in DatabricksRuntimeVersion.parse (#24353, @PattaraS)
• [Evaluation / Tracing] Fix basic-auth before-request validators invoking view functions (#24354, @joshuawong-db)
• [UI] Fix promo modal focus (aria-hidden) and show it on the empty models page (#24278, @aminehd)
• [Scoring] Fix spark_udf InvalidVersion on Databricks Serverless for {major}.x runtime image strings (#24336, @PattaraS)
• [Tracing] Fix trace OTLP encoding for lone surrogates (#24318, @sanatb187)
• [Model Registry / Models] Forward tags to registered ModelVersion in Model.log() (#24271, @Ankita7033)
• [Tracing / UI] Fix duplicate full-trace fetch for TRACKING_STORE traces in the trace UI (#24319, @PattaraS)
• [Models / Scoring] Honor declared ONNX execution providers at load time (#24232, @qyc)
• [Evaluation] Fix pos_label not propagated to evaluate ROC/PR/calibration curves (#24049, @immu4989)
• [Tracking] Resolve experiment id from workspace-prefixed artifact paths in auth proxy (#24214, @rakshithbk-moeng)
• [] Fix DatabricksSDKModelsArtifactRepository auth on serverless executors (#24247, @harupy)
• [Evaluation] Send strict-compatible response_format for AI Gateway judges and scorers (#24048, @B-Step62)
• [Model Registry] Require read permission on the source run or model when creating a model version (#24293, @PattaraS)
• [] Fix Vertex AI Gemini multi-turn tool calling (#24266, @joshuawong-db)
• [Tracking] Enforce update-run authorization on the LogInputs endpoint (#24291, @PattaraS)
• [Tracking] Honor MLFLOW_S3_IGNORE_TLS in multipart artifact upload (#24113, @yashmahamulkar)
• [Gateway / Tracking] Reject non-HTTP scopes in WSGI mount to fix WebSocket crash (#24274, @joshuawong-db)
• [Model Registry / Tracing / Tracking] Fix tracing provider thread leak and set_experiment silently re-enabling tracing (#24267, @PattaraS)
• [Tracing] Fix @mlflow/opencode dropping session metadata against published core (#24252, @joshuawong-db)
• [UI] [BUG] Fix #24170: surface direct (per-resource) permissions in Admin UI (#24253, @nghessss)
• [Model Registry] Fix DNS-rebinding SSRF bypass in webhook delivery (#24258, @PattaraS)
• [Tracing / Tracking] Fix Summary ignoring valid=False Assessments (#24251, @joshuawong-db)
• [Evaluation] Route DSPy judge optimizer Databricks models to Mosaic AI Gateway for Unity Catalog names (#24177, @veronicalyu320)
• [UI] Allow granting of tool call permissions on MLflow assistant (#24084, @joshuawong-db)
• [Build] Fix Python 3.14 compatibility in skill_installer by using pathlib.Path (#24103, @krishtyagi0109-pixel)
• [UI] Render playground tool-call args and JSON responses as code blocks (#24086, @tanghaoji)
• [Gateway] Support Gemini thought signature in AI Gateway (#24051, @vatsalyd)
• [UI] fix(playground): render tool_calls so prompts run with tools no longer show empty result (#24073, @tanghaoji)

Documentation updates:

• [Docs] Add documentation for MCP Registry feature (#24713, @dkuc)
• [Docs / Tracing] docs: troubleshoot $0 trace cost for unknown model names (#24705, @daniellok-db)
• [Docs] docs: credential-expiry trace-drop cause in tracing FAQ, experiment_id in quickstart (#24692, @adamgurary)
• [Docs] Add Swagger UI API docs for MCP Server Registry (#24519, @dkuc)
• [Docs] docs: update auth REST API docs to reflect new RBAC endpoints (#23965, @Farzah11)
• [Docs] docs: fix broken auth REST API links causing Access Denied (#24280) (#24350, @Farzah11)
• [Docs] Add Artifact Hub repository metadata and OCI install docs for the Helm chart (#24313, @B-Step62)
• [Docs] docs: update Omnigent integration page for pure OTel setup (#24240, @TomeHirata)
• [Docs] docs: add Omnigent tracing integration page (#24072, @TomeHirata)

Small bug fixes and documentation updates:

#24746, #24747, #24671, #24637, #24655, #24459, #24510, #24629, #24426, #24554, #24555, #24556, #24359, #24460, #24445, #23676, #24446, #24268, #24417, #24358, #24288, #24250, #24206, #24165, #23939, #23936, #23881, @joshuawong-db; #24743, #24723, #24720, #24694, #24695, #24706, #24698, #24693, #24636, #24675, #24673, #24672, #24663, #24632, #24630, #24628, #24627, #24625, #24548, #24216, #24208, #24205, #24158, #24159, #24136, #24095, #24119, #24106, #24104, #24085, @harupy; #24736, @henishborad; #24717, #24583, #24582, #24584, #24685, #24621, #24604, #24521, #24482, #24495, #24484, #24480, #24481, #24490, #24374, #24317, #24299, @B-Step62; #24656, @rrioh; #24696, #24600, #24601, @daniellok-db; #24657, @DaoDaoNoCode; #24217, @nananosirova; #24645, #24377, #24492, #24380, #21417, #24346, #24297, #24108, @mprahl; #24477, @dkuc; #24572, #24520, #24479, @jonburdo; #24505, @PattaraS; #24242, @Killian-fal; #24558, #24540, #24090, #24139, #24089, #24061, #24032, #24030, @aaronteo-db; #24176, @zcin; #24412, @AknA13; #24437, @smoorjani; #24361, @sun-andsky; #23873, @WeichenXu123; #24240, #24203, #24178, @TomeHirata; #24225, #24204, #24166, #24054, @tanghaoji; #23794, #24171, @kramaranya; #23251, @aakankshaduggal; #24151, #24150, @xq-yin; #24075, @kevin-lyn

MCP Registry

Model Context Protocol servers are quickly becoming the connective tissue between agents and the tools they use — but until now, keeping track of them meant passing around config snippets and hoping everyone had the right version. The new MCP Registry gives you a single, centralized catalog to register, version, and share MCP servers across your team.

Every server gets semantic-versioned configs, promotable aliases (think @production and @staging), and tags for easy organization. MLflow auto-discovers each server's tools so you always know what a given version exposes, and it generates ready-made connection instructions for both Claude Code and .mcp.json — copy, paste, and you're connected. Manage the whole thing however you prefer: through the UI, the REST API, or Python.

A Smarter, Easier MLflow Assistant

The MLflow Assistant just got a major upgrade, and the theme is simple: less setup, more power.

• Bring your own model. The Assistant now supports multiple LLM providers — Claude Code, Codex, and API/Gateway endpoints — all selectable from a single settings page. Use the model that fits your workflow.
• Setup in seconds. Getting started is now as easy as pasting an API key directly into the pane. MLflow stores it securely in the Gateway's LLM Connections, so there's no fiddling with environment variables or config files.
• Full transparency as it works. Tool calls, approvals, and token costs are now displayed inline, so you can see exactly what the Assistant is doing — and what it's costing you — as it happens.

Shareable Table Views

Everyone builds their Runs table a little differently — the columns that matter, the sort order, the filters that cut through the noise. In 3.15.0, you can capture all of it. Save a named view that remembers your columns, their order and widths, your filters, and your sort — then share it with a teammate by simply sending them the URL. No more "here's how to set up your table" walkthroughs; just send the link.

Proxy-less Artifact Upload & Download

Large artifact transfers no longer have to funnel through the tracking server. Using presigned URLs, MLflow can now talk directly to your cloud storage (e.g. S3), cutting server load and eliminating the timeouts that plagued big-file uploads and downloads. It's faster for you and lighter on your infrastructure — and if presigned URLs aren't available, MLflow automatically falls back to the proxied transfer path, so existing setups keep working without any changes.

Multimodal Attachments in LLM Judges

LLM judges have been great for evaluating text — but a lot of real-world agents work with images, screenshots, and other visual content. Now your judges can see them too. {{ trace }} judges created with make_judge() gain a new get_span_image tool that fetches image attachments captured in trace spans, encodes them as base64 data URLs, and passes them straight to a multimodal model.

With support for Anthropic, Gemini, and OpenAI-compatible models (via litellm), you can now write judges that evaluate vision tasks, assess generated or captured screenshots, and reason about any visual content flowing through your traces — unlocking a whole new class of automated evaluation.

Full Changelog

For a comprehensive list of changes, see the release change log.