MLflow Files

MLflow 3.5.0 includes several major features and improvements!

Major Features

• ⚙️ Job Execution Backend: Introduced a new job execution backend infrastructure for running asynchronous tasks with individual execution pools, job search capabilities, and transient error handling. (#17676, [#18012], [#18070], [#18071], [#18112], [#18049], @WeichenXu123)
• 🎯 Flexible Prompt Optimization API: Introduced a new flexible API for prompt optimization with support for model switching and the GEPA algorithm, enabling more efficient prompt tuning with fewer rollouts. See the documentation to get started. (#18183, [#18031], @TomeHirata)
• 🎨 Enhanced UI Onboarding: Improved in-product onboarding experience with trace quickstart drawer and updated homepage guidance to help users discover MLflow's latest features. (#18098, [#18187], @B-Step62)
• 🔐 Security Middleware for Tracking Server: Added a security middleware layer to protect against DNS rebinding, CORS attacks, and other security threats. Read the documentation for configuration details. (#17910, @BenWilson2)

Features

• [Tracing / Tracking] Add unlink_traces_from_run batch operation (#18316, @harupy)
• [Tracing] Add batch trace link/unlink operations to DatabricksTracingRestStore (#18295, @harupy)
• [Tracking] Claude Code SDK autologging support (#18022, @smoorjani)
• [Tracing] Add support for reading trace configuration from environment variables (#17792, @joelrobin18)
• [Tracking] Mistral tracing improvements (#16370, @joelrobin18)
• [Tracking] Gemini token count tracking (#16248, @joelrobin18)
• [Tracking] Gemini streaming support (#16249, @joelrobin18)
• [Tracking] CrewAI token count tracking with documentation updates (#16373, @joelrobin18)
• [Evaluation] Allow passing empty scorer list for manual result comparison (#18265, @B-Step62)
• [Evaluation] Log assessments to DSPy evaluation traces (#18136, @B-Step62)
• [Evaluation] Add support for trace inputs to built-in scorers (#17943, @BenWilson2)
• [Evaluation] Add synonym handling for built-in scorers (#17980, @BenWilson2)
• [Evaluation] Add span timing tool for Agent Judges (#17948, @BenWilson2)
• [Evaluation] Allow disabling evaluation sample check (#18032, @B-Step62)
• [Evaluation] Reduce verbosity of SIMBA optimizer logs when aligning judges (#17795, @BenWilson2)
• [Evaluation] Add __repr__ method for Judges (#17794, @BenWilson2)
• [Prompts] Add prompt registry support to MLflow webhooks (#17640, @harupy)
• [Prompts] Prompt Registry Chat UI (#17334, @joelrobin18)
• [UI] Delete parent and child runs together (#18052, @joelrobin18)
• [UI] Added move to top, move to bottom for charts (#17742, @joelrobin18)
• [Tracking] Use sampling data for run comparison to improve performance (#17645, @lkuo)
• [Tracking] Add optional 'outputs' column for evaluation dataset records (#17735, @WeichenXu123)

Bug Fixes

• [Tracing] Fix parent run resolution mechanism for LangChain (#17273, @B-Step62)
• [Tracing] Add client-side retry for get_trace to improve reliability (#18224, @B-Step62)
• [Tracing] Fix OpenTelemetry dual export (#18163, @B-Step62)
• [Tracing] Suppress false warnings from span logging (#18092, [#18276], @B-Step62)
• [Tracing] Fix OpenTelemetry resource attributes not propagating correctly (#18019, @xiaosha007)
• [Tracing] Fix DSPy prompt display (#17988, @B-Step62)
• [Tracing] Fix usage aggregation to avoid ancestor duplication (#17921, @TomeHirata)
• [Tracing] Fix double counting in Strands tracing (#17855, @joelrobin18)
• [Tracing] Fix to_predict_fn to handle traces without tags field (#17784, @harupy)
• [Tracing] URL-encode trace tag keys in delete_trace_tag to prevent 404 errors (#18232, @copilot-swe-agent)
• [Tracking] Fix Claude Code autologging inputs not displaying (#17858, @smoorjani)
• [Tracking] Fix runs with 0-valued metrics not appearing in experiment list contour plots (#17916, @WeichenXu123)
• [Tracking] Fix DSPy run display (#18137, @B-Step62)
• [Tracking] Allow list of types in tools JSON Schema for OpenAI autolog (#17908, @fedem96)
• [Tracking] Set tracking URI environment variable for job runner (#18073, @WeichenXu123)
• [Evaluation] Add atomicity to job_start API (#18226, @BenWilson2)
• [Evaluation] Fix trace ingest for outputs in merge_records() API (#18047, @BenWilson2)
• [Evaluation] Fix judge regression (#18039, @B-Step62)
• [Evaluation] Fix judges to use non-empty user messages for Anthropic model compatibility (#17935, @dbczumar)
• [Evaluation] Fix endpoints error in judge (#18048, @joelrobin18)
• [Model Registry] Fix creating model versions from non-Databricks tracking to Databricks Unity Catalog registry (#18244, @austinwarner-8451)
• [Model Registry] Fix registry URI instantiation for artifact download (#17982, @arpitjasa-db)
• [Model Registry] Include original error details in Unity Catalog model copy failure messages (#17997, @harupy)
• [Model Registry] Fix webhook delivery to exit early for FileStore instances (#18015, @copilot-swe-agent)
• [Prompts] Fix error suppression during prompt alias resolution when allow_missing is set (#17541, @mr-brobot)
• [UI] General UI improvements (#18281, @joelrobin18)
• [Models] Fix dataset issue (#18081, @joelrobin18)
• [Models] Forward dataset name and digest to PolarsDataset's to_evaluation_dataset method (#17886, @sadelcarpio)
• [Build] Fix mlflow server exiting immediately when optional huey package is missing (#18016, @harupy)
• [Scoring] Fix chat completion arguments (#18248, @aravind-segu)

Documentation Updates

• [Docs] Add self-hosted documentation support (#17986, @B-Step62)
• [Docs] Add GitHub feature requests section to GenAI documentation (#18342, @TomeHirata)
• [Docs] Update Claude Code SDK tracing documentation (#18026, @smoorjani)
• [Docs] Add documentation for Analyze Experiment MCP/CLI command (#17978, @nsthorat)
• [Docs] Add deprecation notice for custom prompt judge (#18287, @smoorjani)
• [Docs] Overhaul scorer documentation (#17930, @B-Step62)
• [Docs] Add default optimizer documentation (#17814, @BenWilson2)
• [Docs] Update TypeScript SDK contribution documentation (#17995, @joelrobin18)
• [Docs] Fix Postgres 18+ mount path in documentation (#18192, @soyun11)
• [Docs] Fix typo: correct variable name from max_few_show_examples to max_few_shot_examples (#18246, @srinathmkce)
• [Docs] Replace single quotes with double quotes for Windows compatibility (#18266, @PavithraNelluri)
• [Docs] Fix typo in model registry documentation (#18038, @EddieMG)

Small bug fixes and documentation updates:

[#18349], [#18338], [#18241], [#18319], [#18309], [#18292], [#18280], [#18239], [#18236], [#17786], [#18003], [#17970], [#17898], [#17765], [#17667], @serena-ruan; [#18346], [#17882], @dbrx-euirim; [#18306], [#18208], [#18165], [#18110], [#18109], [#18108], [#18107], [#18105], [#18104], [#18100], [#18099], [#18155], [#18079], [#18082], [#18078], [#18077], [#18083], [#18030], [#18001], [#17999], [#17712], [#17785], [#17756], [#17729], [#17731], [#17733], @daniellok-db; [#18339], [#18291], [#18222], [#18210], [#18124], [#18101], [#18054], [#18053], [#18007], [#17922], [#17823], [#17822], [#17805], [#17789], [#17750], [#17752], [#17760], [#17758], [#17688], [#17689], [#17693], [#17675], [#17673], [#17656], [#17674], @harupy; [#18331], [#18308], [#18303], [#18146], @smoorjani; [#18315], [#18279], [#18310], [#18187], [#18225], [#18277], [#18193], [#18223], [#18209], [#18200], [#18178], [#17574], [#18021], [#18006], [#17944], @B-Step62; [#18290], [#17946], [#17627], @bbqiu; [#18274], @Ninja3047; [#18204], [#17868], [#17866], [#17833], [#17826], [#17835], @TomeHirata; [#18273], [#18043], [#17928], [#17931], [#17936], [#17937], @dbczumar; [#18185], [#18180], [#18174], [#18170], [#18167], [#18164], [#18168], [#18166], [#18162], [#18160], [#18159], [#18157], [#18156], [#18154], [#18148], [#18145], [#18135], [#18143], [#18142], [#18139], [#18132], [#18130], [#18119], [#18117], [#18115], [#18102], [#18075], [#18046], [#18062], [#18042], [#18051], [#18036], [#18027], [#18014], [#18011], [#18009], [#18004], [#17903], [#18000], [#18002], [#17973], [#17993], [#17989], [#17984], [#17968], [#17966], [#17967], [#17962], [#17977], [#17976], [#17972], [#17965], [#17964], [#17963], [#17969], [#17971], [#17939], [#17926], [#17924], [#17915], [#17911], [#17912], [#17904], [#17902], [#17900], [#17897], [#17892], [#17889], [#17888], [#17885], [#17884], [#17878], [#17874], [#17873], [#17871], [#17870], [#17865], [#17860], [#17861], [#17859], [#17857], [#17856], [#17854], [#17853], [#17851], [#17849], [#17850], [#17847], [#17845], [#17846], [#17844], [#17843], [#17842], [#17838], [#17836], [#17834], [#17831], [#17824], [#17828], [#17819], [#17825], [#17817], [#17821], [#17809], [#17807], [#17808], [#17803], [#17800], [#17799], [#17797], [#17793], [#17790], [#17772], [#17771], [#17769], [#17770], [#17753], [#17762], [#17747], [#17749], [#17745], [#17740], [#17734], [#17732], [#17726], [#17723], [#17722], [#17721], [#17719], [#17720], [#17718], [#17716], [#17713], [#17715], [#17710], [#17709], [#17708], [#17707], [#17705], [#17697], [#17701], [#17698], [#17696], [#17695], @copilot-swe-agent; [#18151], [#18153], [#17983], [#18040], [#17981], [#17841], [#17818], [#17776], [#17781], @BenWilson2; [#18068], @alkispoly-db; [#18133], @kevin-lyn; [#17105], [#17717], @joelrobin18; [#17879], @lkuo; [#17996], [#17945], [#17913], @WeichenXu123