Get span by ID
Get a specific span by its ID. See Spans. These endpoints serve spans, the steps inside a trace. Their REST path /traces keeps the old name of this entity.
Authorizations
API key authorization. Pass your API key in the Authorization header as a Bearer token. Both new (gsk_*) and legacy (gsk-) API keys are accepted, e.g. Authorization: Bearer gsk_... or Authorization: Bearer gsk-....
Path Parameters
Span ID
Response
Span retrieved successfully
A span: one step inside a trace, such as a tool call, a retrieval or an LLM call. The schema name and the /traces path still carry the old name of this entity, "trace". The parent trace is inferenceResultId; the parentTraceId field is the parent span, not the trace. Span ids start with trace_, so a trace_ id belongs here and never to a trace.
"trace_123"
"ir_123"
"fetch_user_data"
SPAN, GENERATION, EVENT, AGENT, TOOL, CHAIN, RETRIEVER, EVALUATOR, EMBEDDING, GUARDRAIL "TOOL"
Human-readable description of the operation. Maximum 1MB.
"Fetches user data from the database by ID"
Input parameters passed to the operation
Result returned by the operation. Usually an object; a plain string for retrieval-context spans
Error message if failed
"Connection timeout"
Execution time in milliseconds
45.5
Additional custom metadata
ID of parent span for hierarchical relationships
"trace_parent_123"