> ## Documentation Index > Fetch the complete documentation index at: https://platform.atlan.com/llms.txt > Use this file to discover all available pages before exploring further. # List spans in one of a user's traces ## OpenAPI ````yaml /public-openapi.json get /registry/v1/users/{user_id}/traces/{trace_id}/spans openapi: 3.1.0 info: title: Atlan public API version: current description: >- Public HTTP API reference for Registry, Skills, Agents, outputs, files, MCP servers and tools, and OTLP telemetry ingestion. servers: - url: https://agentgateway.atlan.engineering description: Atlan API base URL security: - bearer: [] tags: - name: Core - name: Skill - name: Agent - name: Files - name: MCP - name: Observability paths: /registry/v1/users/{user_id}/traces/{trace_id}/spans: get: tags: - Core summary: List spans in one of a user's traces operationId: registry.listUserTraceSpans parameters: - name: user_id in: path required: true schema: type: string - name: trace_id in: path required: true schema: type: string - name: limit in: query required: false schema: type: integer format: int32 minimum: 0 - name: cursor in: query required: false schema: type: string - name: fields in: query required: false schema: type: string responses: '200': content: application/json: schema: $ref: '#/components/schemas/registry-SpanListEnvelope' description: HTTP 200 response. '400': content: application/problem+json: schema: allOf: - $ref: '#/components/schemas/registry-ProblemDetails' - type: object required: - code properties: code: type: string enum: - invalid_query - invalid_request description: HTTP 400 response. '401': content: application/problem+json: schema: allOf: - $ref: '#/components/schemas/registry-ProblemDetails' - type: object required: - code properties: code: type: string enum: - alg_mismatch - alg_not_allowed - audience_mismatch - invalid_api_key - missing_identity - missing_org - missing_user - signature_invalid - token_expired - token_malformed - token_missing - token_not_yet_valid - token_rejected - token_service_account_unbound - unknown_account - unknown_key - untrusted_issuer description: HTTP 401 response. '403': content: application/problem+json: schema: allOf: - $ref: '#/components/schemas/registry-ProblemDetails' - type: object required: - code properties: code: type: string enum: - access_denied - account_suspended description: HTTP 403 response. '404': content: application/problem+json: schema: allOf: - $ref: '#/components/schemas/registry-ProblemDetails' - type: object required: - code properties: code: type: string enum: - not_found description: HTTP 404 response. '500': content: application/problem+json: schema: allOf: - $ref: '#/components/schemas/registry-ProblemDetails' - type: object required: - code properties: code: type: string enum: - internal_error description: HTTP 500 response. '503': content: application/problem+json: schema: allOf: - $ref: '#/components/schemas/registry-ProblemDetails' - type: object required: - code properties: code: type: string enum: - auth_unavailable - not_configured - service_overloaded - service_unavailable description: HTTP 503 response. '504': content: application/problem+json: schema: allOf: - $ref: '#/components/schemas/registry-ProblemDetails' - type: object required: - code properties: code: type: string enum: - request_timeout description: HTTP 504 response. security: - bearer: [] components: schemas: registry-SpanListEnvelope: type: object required: - items - page properties: items: type: array items: $ref: '#/components/schemas/registry-SpanViewDto' page: $ref: '#/components/schemas/registry-CursorPage' registry-ProblemDetails: type: object required: - title - status - detail - code properties: code: type: string detail: type: string status: type: integer format: int32 minimum: 0 title: type: string trace_id: type: - string - 'null' registry-SpanViewDto: type: object required: - span_id - trace_id - name - span_type - span_kind - started_at_unix_seconds - span_status properties: attributes: {} command_name: type: - string - 'null' cost: oneOf: - type: 'null' - $ref: '#/components/schemas/registry-CostView' duration_ms: type: - integer - 'null' format: int64 minimum: 0 ended_at_unix_seconds: type: - integer - 'null' format: int64 event_seq: type: - integer - 'null' format: int64 events: {} input: {} mcp_server: type: - string - 'null' metadata: {} model: type: - string - 'null' name: type: string output: {} parent_span_id: type: - string - 'null' provider: type: - string - 'null' service_name: type: - string - 'null' skill_name: type: - string - 'null' skill_version: type: - string - 'null' span_id: type: string span_kind: type: string span_status: $ref: '#/components/schemas/registry-TraceStatus' span_type: type: string started_at_unix_seconds: type: integer format: int64 tool_name: type: - string - 'null' tool_type: type: - string - 'null' trace_id: type: string usage: oneOf: - type: 'null' - $ref: '#/components/schemas/registry-UsageView' registry-CursorPage: type: object required: - limit properties: limit: type: integer format: int32 minimum: 0 next_cursor: type: - string - 'null' registry-CostView: type: object required: - input_cost_usd - output_cost_usd - total_cost_usd properties: input_cost_usd: type: number format: double output_cost_usd: type: number format: double source: type: - string - 'null' total_cost_usd: type: number format: double registry-TraceStatus: type: string enum: - ok - error - unset registry-UsageView: type: object required: - input_tokens - output_tokens - total_tokens - cache_read_tokens - cache_write_tokens properties: cache_read_tokens: type: integer format: int64 cache_write_tokens: type: integer format: int64 input_tokens: type: integer format: int64 output_tokens: type: integer format: int64 total_tokens: type: integer format: int64 securitySchemes: bearer: type: http scheme: bearer bearerFormat: JWT ````