MLflow Tracing
MLflow Tracing is a Databricks ai / ml capability, introduced June 2024.
The observability layer for GenAI apps and agents on Databricks: it records the inputs, outputs, latency, token usage, and cost of every intermediate step of a run - LLM calls, retrievers, tools, sub-agents - and shows them in the MLflow trace explorer, with traces kept in an MLflow experiment or, since 2026, as OpenTelemetry rows in Unity Catalog tables.
- The docs page for watching what your agent does opens with a "Coding agent quickstart" - "Using a coding agent? Paste this prompt" - so the first recommended reader of the tracing documentation is the agent you are about to trace.
- Keep traces in an MLflow experiment and the backend caps you at 100,000 traces per experiment; point the experiment at a Unity Catalog table instead and the same row of the comparison table just says Unlimited.
- Since August 2026 the trace explorer can be redecorated by Genie - you describe the layout you want in plain language and it generates a reusable view with no coding required, which is an AI building the dashboard you use to check on your AI.
Limitations: For traces stored in Unity Catalog: ingestion is initially limited to 200 traces per second per workspace and 100 MB per second per table (a raisable default - ask your account team for more); an experiment can be bound to a Unity Catalog trace location only when it is created; Unity Catalog traces are not supported with Knowledge Assistant or Supervisor Agent; individual traces cannot be deleted (delete rows from the underlying tables with SQL instead); and traces cannot yet be written to a default storage catalog or to storage protected by Private Link. Traces stored in an experiment instead are hard-capped at 100,000 per experiment.
Open in REbricked →- Category
- AI / ML
- Also known as
- Tracing, MLflow traces, trace explorer, unified trace table
- Verified
- 2026-09-20
Sources
- Official Official Databricks / Microsoft docs
- Official Databricks release notes: first mention, June 12, 2024 - listed as a capability of the Mosaic AI Agent Framework (Public Preview)
- Official Databricks release notes: MLflow Tracing is GA (February 25, 2025)
- Official Databricks release notes: Store and query MLflow traces in Unity Catalog (Beta), January 26, 2026
- Official Databricks release notes: MLflow trace storage in Unity Catalog is now in Public Preview (April 30, 2026)
- Official Databricks release notes: MLflow trace storage in Unity Catalog is now generally available (July 16, 2026)
- Official Databricks release notes: Custom trace views in the MLflow trace explorer are in Beta (August 12, 2026)
- Official Databricks docs: the Unity Gateway unified trace table (Beta, August 21, 2026) - every gateway request and response in one Unity Catalog table, in an MLflow-compatible OTel schema
- Official Databricks docs: Store OpenTelemetry traces in Unity Catalog - the recommended store for new and production workloads