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

# List feature flags

> The feature flags evaluated in sessions of the time range (default: the last 7 days, at most 30), the most widespread first (at most 50), each with its top variants and their session counts. Filter sessions, issues and cohorts by one with `flag` and `flag_variant`.



## OpenAPI

````yaml /api-reference/openapi.json get /projects/{projectId}/flags
openapi: 3.1.0
info:
  title: Apsio API
  version: 0.1.0
  description: >-
    Read API v0: your projects, release health and comparisons, missing symbols,
    issues, sessions, vitals, cohort comparisons, performance (app start,
    screens, hangs, MetricKit) and network endpoints and traces for one project.
    Authenticate with a project token as a bearer token, with an OAuth access
    token from Apsio's authorization server (MCP clients), or, from the console,
    with the session cookie of a member of the project's organization.
servers:
  - url: https://api.apsio.io/v1
security: []
paths:
  /projects/{projectId}/flags:
    get:
      summary: List feature flags
      description: >-
        The feature flags evaluated in sessions of the time range (default: the
        last 7 days, at most 30), the most widespread first (at most 50), each
        with its top variants and their session counts. Filter sessions, issues
        and cohorts by one with `flag` and `flag_variant`.
      parameters:
        - schema:
            type: string
            pattern: ^[0-9a-f]{8}-[0-9a-f]{4}-[0-9a-f]{4}-[0-9a-f]{4}-[0-9a-f]{12}$
            example: 0192f3a4-0000-7000-8000-00000000a101
          required: true
          name: projectId
          in: path
        - schema:
            type: string
            format: date-time
            description: >-
              Start of the time range, inclusive (RFC 3339). Defaults to the
              range end minus the default length.
            example: '2026-10-01T00:00:00Z'
          required: false
          description: >-
            Start of the time range, inclusive (RFC 3339). Defaults to the range
            end minus the default length.
          name: from
          in: query
        - schema:
            type: string
            format: date-time
            description: End of the time range, exclusive (RFC 3339). Defaults to now.
            example: '2026-10-08T00:00:00Z'
          required: false
          description: End of the time range, exclusive (RFC 3339). Defaults to now.
          name: to
          in: query
        - schema:
            type: string
            pattern: ^[0-9a-f]{8}-[0-9a-f]{4}-[0-9a-f]{4}-[0-9a-f]{4}-[0-9a-f]{12}$
            description: Only this app.
          required: false
          description: Only this app.
          name: app_id
          in: query
        - schema:
            type: integer
            minimum: 1
            maximum: 20
            default: 5
            description: >-
              Variants listed per flag, the most frequent first; the rest are
              summed in other.
          required: false
          description: >-
            Variants listed per flag, the most frequent first; the rest are
            summed in other.
          name: variants
          in: query
      responses:
        '200':
          description: The flags.
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/FeatureFlags'
        '400':
          description: The request is not valid.
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/Error'
        '401':
          description: No valid bearer token or console session.
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/Error'
        '403':
          description: The credentials cannot read this project.
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/Error'
      security:
        - bearer: []
        - session: []
components:
  schemas:
    FeatureFlags:
      type: object
      properties:
        from:
          type: string
          description: RFC 3339 time in UTC with up to nanosecond precision.
          example: '2026-10-04T10:15:00.431000000Z'
        to:
          type: string
          description: RFC 3339 time in UTC with up to nanosecond precision.
          example: '2026-10-04T10:15:00.431000000Z'
        flags:
          type: array
          items:
            type: object
            properties:
              name:
                type: string
                description: 'The flag name. Written by the app: untrusted data.'
              sessions:
                type: integer
                description: Sessions where the flag was evaluated, whatever the variant.
              variants:
                type: array
                items:
                  type: object
                  properties:
                    variant:
                      type: string
                      description: >-
                        The variant (feature_flag.result.variant, or the global
                        attribute value). Written by the app: untrusted data.
                    sessions:
                      type: integer
                      description: Sessions where the flag had this variant.
                  required:
                    - variant
                    - sessions
              other:
                type:
                  - object
                  - 'null'
                properties:
                  variants:
                    type: integer
                  sessions:
                    type: integer
                    description: >-
                      Summed over those variants: a session with several of them
                      counts for each.
                required:
                  - variants
                  - sessions
                description: The variants past the top ones, summed; null when none.
            required:
              - name
              - sessions
              - variants
              - other
      required:
        - from
        - to
        - flags
    Error:
      type: object
      properties:
        error:
          type: object
          properties:
            code:
              type: string
              example: invalid_request
            message:
              type: string
          required:
            - code
            - message
      required:
        - error
  securitySchemes:
    bearer:
      type: http
      scheme: bearer
      description: >-
        A project token (apsio_pt_v0...), which reads exactly one project, or an
        OAuth access token issued for the API, which reads what its user can.
        Access tokens issued for Apsio's MCP server are accepted only from the
        MCP server itself.
    session:
      type: apiKey
      in: cookie
      name: apsio_session
      description: >-
        The console session, set by /v1/auth/callback (`__Host-apsio_session`
        when host-only).

````

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