Applies to:
Trace level metrics feature flag is enabled. This feature flag aggregates metrics at the trace level rather than span level, preventing span-level filters like is_root = true from working correctly. Disable the Trace level metrics feature flag to restore span-level filtering functionality.
Resolution Steps
If you need span-level filtering to work
Step 1: Navigate to Feature Flags
Go to Settings > Feature flags in your Braintrust account.Step 2: Disable Trace Level Metrics
Find theTrace level metrics feature flag and toggle it to the off position.
Step 3: Verify Filtering Works
Return to the monitoring page and apply your span name filter withis_root = true. The metrics should now filter correctly to show only root-level spans.
If you need trace-level aggregation
Step 1: Understand the Trade-off
WhenTrace level metrics is enabled, the dashboard aggregates metrics at the trace level (entire request/conversation) rather than the span level (individual LLM calls or tool invocations). This means span-level filtering will not work as expected.
Step 2: Use Alternative Filtering
Instead of filtering by span name, use trace-level filters to segment your data. Consider using SQL filters or tag filters on trace-level attributes.Understanding Trace-Level vs Span-Level Metrics
Span-Level Metrics (Default)
WhenTrace level metrics is disabled:
- Metrics aggregate at the individual span level
- Each LLM call, tool invocation, or operation is counted separately
- Filtering by
is_root = trueshows only top-level spans - Useful for analyzing individual operations and their performance
Trace-Level Metrics
WhenTrace level metrics is enabled:
- Metrics aggregate at the trace level (entire request/conversation)
- All spans within a trace are grouped together
- Span-level filters like
is_rootdo not affect aggregation - Useful for analyzing end-to-end request performance