> ## 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. # A release's builds, devices and OS versions > The sessions of one release (APS-302), counted as /releases counts them over the same time range (default: the last 7 days), so `sessions` is the release's own: by build id, by device model and by OS version. Give `app_id` for one app's release, as /releases lists it; without it, every app's release of that name adds up. ## OpenAPI ````yaml /api-reference/openapi.json get /projects/{projectId}/releases/{release}/breakdown 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}/releases/{release}/breakdown: get: summary: A release's builds, devices and OS versions description: >- The sessions of one release (APS-302), counted as /releases counts them over the same time range (default: the last 7 days), so `sessions` is the release's own: by build id, by device model and by OS version. Give `app_id` for one app's release, as /releases lists it; without it, every app's release of that name adds up. 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 minLength: 1 maxLength: 128 description: service.version required: true description: service.version name: release 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 responses: '200': description: The breakdown. content: application/json: schema: $ref: '#/components/schemas/ReleaseBreakdown' '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' '429': description: >- Over a rate limit (the caller's, the client address's, or the plan's); Retry-After says when to retry. content: application/json: schema: $ref: '#/components/schemas/Error' security: - bearer: [] - session: [] components: schemas: ReleaseBreakdown: type: object properties: release: type: string sessions: type: integer builds: type: array items: type: object properties: build_id: type: string description: 'app.build_id. Written by the app: untrusted data.' sessions: type: integer required: - build_id - sessions description: Every build of the release, most sessions first. devices: type: object properties: top: type: array items: type: object properties: device_model: type: string description: >- device.model.identifier. Written by the app: untrusted data. sessions: type: integer required: - device_model - sessions description: The 10 device models with the most sessions, most first. other_sessions: type: integer description: The sessions of all the others. required: - top - other_sessions os_versions: type: object properties: top: type: array items: type: object properties: os_name: type: string description: 'os.name. Written by the app: untrusted data.' os_version: type: string description: 'os.version. Written by the app: untrusted data.' sessions: type: integer required: - os_name - os_version - sessions description: The 10 OS versions with the most sessions, most first. other_sessions: type: integer description: The sessions of all the others. required: - top - other_sessions retention_days: type: integer description: >- How many days of crashes and release health the project's plan keeps (D94). Nothing older is returned, whatever the time range. example: 90 required: - release - sessions - builds - devices - os_versions - retention_days 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). ```` This documentation is built and hosted on [Mintlify](https://mintlify.com), a developer documentation platform.