project_namestring
If null, the default project is used
parent_span_idstring uuid
type'general' | 'tool' | 'llm' | 'guardrail'
start_timestring date-time required
outputJsonListStringWrite
metadataJsonListStringWrite
last_updated_atstring date-time
total_estimated_costnumber
total_estimated_cost_versionstring
ttftnumber double
Time to first token in milliseconds
source'sdk' | 'experiment' | 'playground' | 'optimization' | 'evaluator'