PromptLayer

PromptLayer Spans & Traces API

Ingest spans and manage traces for LLM observability.

GitHub OpenAPI

Documentation

📖
Documentation
https://docs.promptlayer.com/why-promptlayer/how-it-works
📖
APIReference
https://docs.promptlayer.com/reference/log-request
📖
Documentation
https://docs.promptlayer.com/features/prompt-registry
📖
APIReference
https://docs.promptlayer.com/reference/get-prompt-template
📖
Documentation
https://docs.promptlayer.com/features/evaluations/overview
📖
APIReference
https://docs.promptlayer.com/reference/list-evaluations
📖
Documentation
https://docs.promptlayer.com/features/tracing
📖
APIReference
https://docs.promptlayer.com/reference/spans-bulk

Specifications

⚙
OpenAPI
https://raw.githubusercontent.com/api-evangelist/promptlayer/refs/heads/main/openapi/promptlayer-spans-traces-api-openapi.yml

Other Resources

🔗
PostmanCollection
https://raw.githubusercontent.com/api-evangelist/promptlayer/refs/heads/main/collections/promptlayer.postman_collection.json

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OpenAPI Specification

promptlayer-spans-traces-api-openapi.yml Raw ↑ 
openapi: 3.0.1
info:
  title: PromptLayer Evaluations & Datasets Spans & Traces API
  description: 'REST API for PromptLayer, a prompt engineering, prompt management, and LLM observability platform. The API logs and tracks LLM requests, manages a versioned prompt registry with release labels, ingests OpenTelemetry-style spans and traces, and runs evaluations against datasets. All requests are authenticated with an `X-API-KEY` header. Note: some legacy tracking endpoints are served under the `/rest` path prefix while newer endpoints are served at the API root.'
  termsOfService: https://www.promptlayer.com/terms-of-service
  contact:
    name: PromptLayer Support
    email: hello@promptlayer.com
  version: '1.0'
servers:
- url: https://api.promptlayer.com
security:
- ApiKeyAuth: []
tags:
- name: Spans & Traces
  description: Ingest spans and manage traces for LLM observability.
paths:
  /spans-bulk:
    post:
      operationId: createSpansBulk
      tags:
      - Spans & Traces
      summary: Ingest spans in bulk
      description: Atomically ingests a batch of OpenTelemetry-style spans. Optional per-span `log_request` payloads create associated request logs. If any span fails, the entire batch is rolled back.
      requestBody:
        required: true
        content:
          application/json:
            schema:
              $ref: '#/components/schemas/SpansBulkRequest'
      responses:
        '201':
          description: Spans ingested
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/SpansBulkResponse'
        '401':
          description: Unauthorized
        '422':
          description: Validation error
  /otlp/v1/traces:
    post:
      operationId: ingestOtlpTraces
      tags:
      - Spans & Traces
      summary: Ingest OTLP traces
      description: OpenTelemetry Protocol (OTLP) HTTP endpoint for ingesting traces.
      requestBody:
        required: true
        content:
          application/json:
            schema:
              type: object
              additionalProperties: true
      responses:
        '200':
          description: Traces accepted
        '401':
          description: Unauthorized
  /traces/{id}:
    get:
      operationId: getTrace
      tags:
      - Spans & Traces
      summary: Get a trace
      parameters:
      - name: id
        in: path
        required: true
        schema:
          type: string
      responses:
        '200':
          description: A trace
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/Trace'
        '401':
          description: Unauthorized
        '404':
          description: Not found
  /traces/{id}/close:
    post:
      operationId: closeTrace
      tags:
      - Spans & Traces
      summary: Close a trace
      description: Closes an open trace so no further spans can be appended.
      parameters:
      - name: id
        in: path
        required: true
        schema:
          type: string
      responses:
        '200':
          description: Trace closed
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/SuccessMessage'
        '401':
          description: Unauthorized
        '404':
          description: Not found
components:
  schemas:
    PromptBlueprint:
      type: object
      description: Prompt Blueprint payload, either a chat prompt (messages array) or a completion prompt (content string). Provider-agnostic representation.
      additionalProperties: true
    Trace:
      type: object
      properties:
        id:
          type: string
        name:
          type: string
        spans:
          type: array
          items:
            $ref: '#/components/schemas/Span'
        closed:
          type: boolean
    Span:
      type: object
      properties:
        name:
          type: string
        context:
          type: object
          properties:
            trace_id:
              type: string
            span_id:
              type: string
            trace_state:
              type: string
        kind:
          type: string
          enum:
          - SpanKind.CLIENT
          - SpanKind.CONSUMER
          - SpanKind.INTERNAL
          - SpanKind.PRODUCER
          - SpanKind.SERVER
        parent_id:
          type: string
          nullable: true
        start_time:
          type: integer
          description: Start time in nanoseconds.
        end_time:
          type: integer
          description: End time in nanoseconds.
        status:
          type: object
          properties:
            status_code:
              type: string
              enum:
              - StatusCode.OK
              - StatusCode.ERROR
              - StatusCode.UNSET
            description:
              type: string
              nullable: true
        attributes:
          type: object
          additionalProperties: true
        resource:
          type: object
          properties:
            attributes:
              type: object
              additionalProperties: true
            schema_url:
              type: string
        log_request:
          $ref: '#/components/schemas/LogRequest'
    SpansBulkRequest:
      type: object
      required:
      - spans
      properties:
        spans:
          type: array
          items:
            $ref: '#/components/schemas/Span'
        close_after:
          type: boolean
          default: false
    SuccessMessage:
      type: object
      properties:
        success:
          type: boolean
        message:
          type: string
    SpansBulkResponse:
      type: object
      properties:
        success:
          type: boolean
        spans:
          type: array
          items:
            type: object
            properties:
              id:
                type: integer
              name:
                type: string
              span_id:
                type: string
        request_logs:
          type: array
          items:
            type: object
            properties:
              id:
                type: integer
              span_id:
                type: string
        rejected_span_ids:
          type: array
          nullable: true
          items:
            type: string
        rejected_trace_ids:
          type: array
          nullable: true
          items:
            type: string
        rejection_reason:
          type: string
          nullable: true
    LogRequest:
      type: object
      required:
      - provider
      - model
      - input
      - output
      - request_start_time
      - request_end_time
      properties:
        provider:
          type: string
          description: LLM provider name (e.g., openai, anthropic).
        model:
          type: string
          description: Model identifier.
        input:
          $ref: '#/components/schemas/PromptBlueprint'
        output:
          $ref: '#/components/schemas/PromptBlueprint'
        request_start_time:
          type: string
          format: date-time
        request_end_time:
          type: string
          format: date-time
        api_type:
          type: string
          description: API endpoint type (e.g., chat-completions).
        parameters:
          type: object
          additionalProperties: true
          description: Model parameters such as temperature and max_tokens.
        tags:
          type: array
          items:
            type: string
        metadata:
          type: object
          additionalProperties:
            type: string
        status:
          type: string
          enum:
          - SUCCESS
          - WARNING
          - ERROR
          default: SUCCESS
        error_type:
          type: string
        error_message:
          type: string
          maxLength: 1024
        input_tokens:
          type: integer
        output_tokens:
          type: integer
        price:
          type: number
        score:
          type: integer
          minimum: 0
          maximum: 100
  securitySchemes:
    ApiKeyAuth:
      type: apiKey
      in: header
      name: X-API-KEY