> ## Documentation Index > Fetch the complete documentation index at: https://docs.usetuner.ai/llms.txt > Use this file to discover all available pages before exploring further. # Get Call Spans > Retrieve a call's OpenTelemetry spans, flat and in start-time order. Returns an empty list when the call has no trace, which is the common case — whether spans exist depends on how the customer's agent is instrumented. ## OpenAPI ````yaml https://api.usetuner.ai/public/openapi.json get /api/v1/workspaces/{workspace_id}/agents/{agent_id}/calls/{call_id}/spans openapi: 3.1.0 info: title: My Public API version: 1.0.0 servers: - url: https://api.usetuner.ai security: [] tags: - name: calls x-group: Calls - name: workspaces x-group: Workspaces - name: agent-settings x-group: Agent Settings - name: agents x-group: Agents - name: simulation x-group: Simulation - name: traces x-group: Traces - name: providers x-group: Providers paths: /api/v1/workspaces/{workspace_id}/agents/{agent_id}/calls/{call_id}/spans: get: tags: - calls - calls summary: Get Call Spans description: >- Retrieve a call's OpenTelemetry spans, flat and in start-time order. Returns an empty list when the call has no trace, which is the common case — whether spans exist depends on how the customer's agent is instrumented. operationId: >- get_call_spans_api_v1_workspaces__workspace_id__agents__agent_id__calls__call_id__spans_get parameters: - name: call_id in: path required: true schema: type: integer description: Tuner's internal numeric ID for the call. title: Call Id description: Tuner's internal numeric ID for the call. - name: agent_id in: path required: true schema: type: integer description: Tuner's internal numeric ID for the agent. title: Agent Id description: Tuner's internal numeric ID for the agent. - name: workspace_id in: path required: true schema: type: integer description: Workspace ID. Find this in Workspace > General Settings. title: Workspace Id description: Workspace ID. Find this in Workspace > General Settings. responses: '200': description: Successful Response content: application/json: schema: type: array items: $ref: '#/components/schemas/CallSpanResponse' title: >- Response Get Call Spans Api V1 Workspaces Workspace Id Agents Agent Id Calls Call Id Spans Get '401': description: Missing or invalid API key. content: application/json: example: detail: Not authenticated schema: $ref: '#/components/schemas/ErrorResponse' '403': description: You do not have access to this workspace. content: application/json: example: detail: User does not have access to workspace 42 schema: $ref: '#/components/schemas/ErrorResponse' '404': description: Agent or call not found. content: application/json: example: detail: Call with ID 88 not found schema: $ref: '#/components/schemas/ErrorResponse' '422': description: Validation Error content: application/json: schema: $ref: '#/components/schemas/HTTPValidationError' security: - Bearer: [] components: schemas: CallSpanResponse: properties: span_id: type: string title: Span Id description: This span's id, hex parent_span_id: anyOf: - type: string - type: 'null' title: Parent Span Id description: Owning span's id, hex. Null on the root span. trace_id: type: string title: Trace Id description: Id of the trace this span belongs to, hex name: type: string title: Name description: Operation name, e.g. 'llm' or 'agent_turn' kind: anyOf: - type: integer - type: 'null' title: Kind description: OpenTelemetry span kind start_time: type: string format: date-time title: Start Time description: When the operation started end_time: type: string format: date-time title: End Time description: When the operation finished duration_ms: anyOf: - type: number - type: 'null' title: Duration Ms description: Duration in milliseconds status_code: type: integer title: Status Code description: 'OpenTelemetry status: 0 unset, 1 ok, 2 error' status_message: anyOf: - type: string - type: 'null' title: Status Message description: Status detail, when the span failed scope_name: anyOf: - type: string - type: 'null' title: Scope Name description: Library that emitted the span service_name: anyOf: - type: string - type: 'null' title: Service Name description: Emitting service, e.g. 'livekit-agents' attributes: additionalProperties: true type: object title: Attributes description: Allowlisted span attributes resource_attributes: additionalProperties: true type: object title: Resource Attributes description: Allowlisted attributes describing the emitting process type: object required: - span_id - trace_id - name - start_time - end_time - status_code title: CallSpanResponse description: >- One span in a call's trace. Returned flat rather than nested. The client rebuilds the tree from `parent_span_id`, and needs the flat list regardless to position waterfall bars against the overall trace window. `attributes` holds allowlisted keys only — no transcripts, prompts, LLM inputs or outputs, or tool arguments. See app/core/otel_span_allowlist.py. ErrorResponse: properties: detail: type: string title: Detail description: Human-readable description of what went wrong. type: object required: - detail title: ErrorResponse description: Error body returned when a request fails. HTTPValidationError: properties: detail: items: $ref: '#/components/schemas/ValidationError' type: array title: Detail type: object title: HTTPValidationError ValidationError: properties: loc: items: anyOf: - type: string - type: integer type: array title: Location msg: type: string title: Message type: type: string title: Error Type input: title: Input ctx: type: object title: Context type: object required: - loc - msg - type title: ValidationError securitySchemes: Bearer: type: http description: >- Use Tuner API key (tr_api_...) or user session token. Find your API key in Workspace Settings > API Keys. scheme: bearer ````