> ## Documentation Index
> Fetch the complete documentation index at: https://docs.axilio.ai/llms.txt
> Use this file to discover all available pages before exploring further.

# List phone sessions with cost

> Paginated, filterable list of the caller's phone sessions over a required time window (start_date/end_date), each row carrying billing detail: phone-time cost, inference cost, and combined total in microdollars, billing processing status, and allocation source. Filters: session status, billing processing status, workflow, allocation source, free-text search. Order with order_by ('<field> <asc|desc>').



## OpenAPI

````yaml /api-reference/openapi-backend.json get /usage/sessions
openapi: 3.1.0
info:
  description: Axilio backend HTTP API.
  title: Axilio API
  version: 0.85.0
servers:
  - url: https://api.axilio.ai/api/v1
    description: Production
security: []
tags:
  - name: API Keys
  - name: Billing
  - name: Files
  - name: Organization
  - name: Phones
  - name: Runs
  - name: Skill
  - name: Usage
  - name: Workflows
paths:
  /usage/sessions:
    get:
      tags:
        - Usage
      summary: List phone sessions with cost
      description: >-
        Paginated, filterable list of the caller's phone sessions over a
        required time window (start_date/end_date), each row carrying billing
        detail: phone-time cost, inference cost, and combined total in
        microdollars, billing processing status, and allocation source. Filters:
        session status, billing processing status, workflow, allocation source,
        free-text search. Order with order_by ('<field>
        <asc|desc>').
      operationId: usage_list_sessions
      parameters:
        - description: Beginning of the sessions query window (RFC 3339).
          explode: false
          in: query
          name: start_date
          required: true
          schema:
            description: Beginning of the sessions query window (RFC 3339).
            format: date-time
            type: string
        - description: End of the sessions query window (RFC 3339).
          explode: false
          in: query
          name: end_date
          required: true
          schema:
            description: End of the sessions query window (RFC 3339).
            format: date-time
            type: string
        - description: Number of sessions per page (1-100).
          explode: false
          in: query
          name: limit
          schema:
            default: 50
            description: Number of sessions per page (1-100).
            format: int64
            maximum: 100
            minimum: 1
            type: integer
        - description: Pagination offset.
          explode: false
          in: query
          name: offset
          schema:
            default: 0
            description: Pagination offset.
            format: int64
            minimum: 0
            type: integer
        - description: Restrict results to the given session lifecycle statuses.
          explode: false
          in: query
          name: session_status_filter
          schema:
            description: Restrict results to the given session lifecycle statuses.
            items:
              type: string
            type:
              - array
              - 'null'
        - description: Restrict results to the given billing processing statuses.
          explode: false
          in: query
          name: processed_status_filter
          schema:
            description: Restrict results to the given billing processing statuses.
            items:
              type: string
            type:
              - array
              - 'null'
        - description: Restrict results to sessions of a single workflow.
          explode: false
          in: query
          name: workflow_id
          schema:
            description: Restrict results to sessions of a single workflow.
            type: string
        - description: Restrict results to the given allocation sources.
          explode: false
          in: query
          name: allocated_by
          schema:
            description: Restrict results to the given allocation sources.
            items:
              type: string
            type:
              - array
              - 'null'
        - description: Filter by session, workflow, or phone id substring.
          explode: false
          in: query
          name: search
          schema:
            description: Filter by session, workflow, or phone id substring.
            type: string
        - description: >-
            Sort expression '<field> <asc|desc>'; field one of
            allocated_at, deallocated_at, duration, cost_microdollars,
            session_status, processed_status, allocated_by, session_id,
            workflow_id. Defaults to allocated_at desc.
          explode: false
          in: query
          name: order_by
          schema:
            description: >-
              Sort expression '<field> <asc|desc>'; field one of
              allocated_at, deallocated_at, duration, cost_microdollars,
              session_status, processed_status, allocated_by, session_id,
              workflow_id. Defaults to allocated_at desc.
            type: string
      responses:
        '200':
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/UsageSessionsResponse'
          description: OK
        default:
          content:
            application/problem+json:
              schema:
                $ref: '#/components/schemas/V2ErrorModel'
          description: Error
      security:
        - apiKeyAuth: []
components:
  schemas:
    UsageSessionsResponse:
      additionalProperties: false
      description: Paginated list of phone sessions.
      properties:
        limit:
          description: Page size used for this response.
          format: int64
          type: integer
        offset:
          description: Pagination offset used for this response.
          format: int64
          type: integer
        sessions:
          description: Page of session records.
          items:
            $ref: '#/components/schemas/UsageSession'
          type:
            - array
            - 'null'
        total:
          description: Total number of sessions matching the query.
          format: int64
          type: integer
      required:
        - sessions
        - total
        - limit
        - offset
      type: object
    V2ErrorModel:
      additionalProperties: false
      description: >-
        Error response, following RFC 9457 (Problem Details for HTTP APIs).
        Returned with a application/problem+json content type.
      properties:
        detail:
          description: >-
            A human-readable explanation specific to this occurrence of the
            problem.
          examples:
            - Property foo is required but is missing.
          type: string
        errors:
          description: Optional list of individual error details
          items:
            $ref: '#/components/schemas/V2ErrorDetail'
          type:
            - array
            - 'null'
        instance:
          description: >-
            A URI reference that identifies the specific occurrence of the
            problem.
          examples:
            - https://example.com/error-log/abc123
          format: uri
          type: string
        status:
          description: HTTP status code
          examples:
            - 400
          format: int64
          type: integer
        title:
          description: >-
            A short, human-readable summary of the problem type. This value
            should not change between occurrences of the error.
          examples:
            - Bad Request
          type: string
        type:
          default: about:blank
          description: A URI reference to human-readable documentation for the error.
          examples:
            - https://example.com/errors/example
          format: uri
          type: string
      type: object
    UsageSession:
      additionalProperties: false
      description: Single phone-session record from the usage sessions endpoint.
      properties:
        allocated_at:
          description: ISO 8601 timestamp when the phone was allocated.
          type: string
        allocated_by:
          description: AllocatedBy identifies what triggered the session's allocation.
          type: string
        billing_plan_id:
          description: Billing plan active during the session.
          type: string
        cost_microdollars:
          description: Phone-time cost charged for this session in microdollars.
          format: int64
          type: integer
        deallocated_at:
          description: ISO 8601 timestamp when the phone was released.
          type: string
        duration_seconds:
          description: Session duration in seconds.
          format: int64
          type: integer
        inference_cost_microdollars:
          description: >-
            Inference spend attributable to this session (sum of the argus calls
            made under it).
          format: int64
          type: integer
        is_dedicated_phone:
          description: Whether the session used a dedicated pre-paid phone.
          type: boolean
        phone_id:
          description: Phone claimed by the session.
          type: string
        processed_status:
          description: Billing processing status (e.g., 'billed').
          type: string
        session_id:
          description: Unique session identifier.
          type: string
        session_metadata:
          additionalProperties: {}
          description: Arbitrary metadata attached to the session.
          type: object
        session_status:
          description: Session lifecycle status (e.g., 'completed').
          type: string
        total_cost_microdollars:
          description: 'Session''s all-in cost: phone time + inference.'
          format: int64
          type: integer
        workflow_id:
          description: Associated workflow identifier.
          type: string
      required:
        - session_id
        - workflow_id
        - phone_id
        - cost_microdollars
        - inference_cost_microdollars
        - total_cost_microdollars
        - is_dedicated_phone
      type: object
    V2ErrorDetail:
      additionalProperties: false
      description: >-
        One specific problem within an error response, locating the offending
        part of the request.
      properties:
        location:
          description: >-
            Where the error occurred, e.g. 'body.items[3].tags' or
            'path.thing-id'
          type: string
        message:
          description: Error message text
          type: string
        value:
          description: The value at the given location
      type: object
  securitySchemes:
    apiKeyAuth:
      description: Customer API key (axl_ prefix).
      in: header
      name: X-Axilio-Api-Key
      type: apiKey

````

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