Speech-To-Text-With-Databricks: Skill for Claude Code

Analyzing a Single MLflow Trace

Trace Structure

A trace captures the full execution of an AI/ML application as a tree of spans. Each span represents one operation (LLM call, tool invocation, retrieval step, etc.) and records its inputs, outputs, timing, and status. Traces also carry assessments — feedback from humans or LLM judges about quality.

It is recommended to read references/trace-structure.md before analyzing a trace — it covers the complete data model, all fields and types, analysis guidance, and OpenTelemetry compatibility notes.

Handling CLI Output

Traces can be 100KB+ for complex agent executions. Always redirect output to a file — do not pipe mlflow traces get directly to jq, head, or other commands, as piping can silently produce no output.

# Fetch full trace to a file (traces get always outputs JSON, no --output flag needed)
mlflow traces get --trace-id <ID> > /tmp/trace.json

# Then process the file
jq '.info.state' /tmp/trace.json
jq '.data.spans | length' /tmp/trace.json

Prefer fetching the full trace and parsing the JSON directly rather than using --extract-fields. The --extract-fields flag has limited support for nested span data (e.g., span inputs/outputs may return empty objects). Fetch the complete trace once and parse it as needed.

JSON Structure

The trace JSON has two top-level keys: info (metadata, assessments) and data (spans).

{
  "info": { "trace_id", "state", "request_time", "assessments", ... },
  "data": { "spans": [ { "span_id", "name", "status", "attributes", ... } ] }
}

Key paths (verified against actual CLI output):

What	jq path
Trace state	.info.state
All spans	.data.spans
Root span	.data.spans[] | select(.parent_span_id == null)
Span status code	.data.spans[].status.code (values: STATUS_CODE_OK, STATUS_CODE_ERROR, STATUS_CODE_UNSET)
Span status message	.data.spans[].status.message
Span inputs	.data.spans[].attributes["mlflow.spanInputs"]
Span outputs	.data.spans[].attributes["mlflow.spanOutputs"]
Assessments	.info.assessments
Assessment name	.info.assessments[].assessment_name
Feedback value	.info.assessments[].feedback.value
Feedback error	.info.assessments[].feedback.error
Assessment rationale	.info.assessments[].rationale