> ## Documentation Index > Fetch the complete documentation index at: https://docs.halfpagetechnologies.com/llms.txt > Use this file to discover all available pages before exploring further. # List available models > List the segmentation models available to your organization. Includes every shared public base model (e.g. `cpsam`) plus the custom models your organization has trained in the dashboard. Use a returned `id` as the `model_id` when running a prediction with `POST /predict`. ## OpenAPI ````yaml /api-reference/openapi.json get /api/v1/models openapi: 3.1.0 info: title: HalfPage API description: > The **HalfPage API** runs Cellpose-based cell segmentation on your microscopy images programmatically — upload an image, run a prediction, and export the resulting cell masks, ROIs, and measurements. ## Base URL ``` https://api.halfpagetechnologies.com/backend/api/v1 ``` Every path in this reference is relative to that base URL. A staging environment is available at `https://staging-api.halfpagetechnologies.com/backend/api/v1`. ## Authentication Authenticate every request with an API key in the `Authorization` header as a bearer token: ``` Authorization: Bearer hp_live_xxxxxxxxxxxxxxxxxxxxxxxx ``` Create and manage keys from the **API Keys** section of the HalfPage dashboard — keys cannot be minted through the API. A key is scoped to the organization that owns it; every resource you create or read is confined to that organization. Requests without a valid key receive `401`; a valid key used against an endpoint outside the public product surface receives `403`. ## Core workflow Three steps — **upload, predict, export** — plus a model list to choose from. Segmentation runs asynchronously on GPU workers, so step 2 is poll-based: 1. **Upload an image** (`POST /upload`) as `multipart/form-data` with a `file` part. One call: the image record is created for you and the response returns it already `ready`, with the `image.id` for the next step. *(Large file or flaky connection? POST the same endpoint as `application/json` with `{"name": ..., "size": ...}` instead. You get back presigned part URLs — PUT the chunks, call `POST /upload/{image_id}/complete`, then poll `GET /upload/{image_id}` until `upload_status` is `ready`.)* 2. **Pick a model** (`GET /models`) and **run a prediction** (`POST /predict`) with the `image_id` and a `model_id`. That returns a `prediction_id`; poll `GET /predict/{prediction_id}` until `status` is `COMPLETED`. The response then carries a `segmentation_id` and the `cell_count` detected. 3. **Export** that segmentation as CSV measurements (`GET /export/{segmentation_id}/measurements.csv`), GeoJSON ROIs (`.../rois.geojson`), or an ImageJ ROI archive (`.../rois.zip`). ## Quotas Uploads and analyses are metered against your plan. Exceeding your image storage cap or monthly analysis cap returns `402` with a human-readable `detail` explaining the limit — upgrade your plan to raise it. version: 1.0.0 servers: - url: https://api.halfpagetechnologies.com/backend description: Production - url: https://staging-api.halfpagetechnologies.com/backend description: Staging security: [] tags: - name: upload description: >- Get microscopy images into HalfPage, and manage them once they are there. `POST /upload` is the only way in and covers both modes: send `multipart/form-data` with a `file` part to upload in one request (the image comes back `ready`), or send `application/json` with `{name, size}` to open a resumable upload and get presigned part URLs back. Resumable uploads finish with `complete` (no ETag bookkeeping needed) and are polled until `ready`. - name: predict description: >- Run segmentation on a ready image and poll it to completion. `POST /predict` queues the run on a GPU worker and returns a `prediction_id`; `GET /predict/{prediction_id}` reports progress and, once `COMPLETED`, the `segmentation_id` and cell count of the result. - name: export description: >- Download a completed segmentation in analysis-ready formats: a CSV of per-cell measurements, a GeoJSON of ROI polygons, or a ZIP of ImageJ-compatible ROIs. The CSV endpoint accepts a `columns` parameter to narrow the output to the measurements you care about. - name: models description: >- List the segmentation models available to your organization — the shared public base models (e.g. `cpsam`) plus any custom models trained in the dashboard — to choose a `model_id` for a prediction. paths: /api/v1/models: get: tags: - models summary: List available models description: >- List the segmentation models available to your organization. Includes every shared public base model (e.g. `cpsam`) plus the custom models your organization has trained in the dashboard. Use a returned `id` as the `model_id` when running a prediction with `POST /predict`. operationId: list_models_api_v1_models_get responses: '200': description: Successful Response content: application/json: schema: items: $ref: '#/components/schemas/ModelSummary' type: array title: Response List Models Api V1 Models Get '401': description: >- Missing or invalid credentials. Supply a valid `Authorization: Bearer hp_live_...` API key. content: application/json: schema: $ref: '#/components/schemas/ErrorResponse' example: detail: Requires authentication '404': description: Not found security: - HTTPBearer: [] components: schemas: ModelSummary: properties: id: type: string title: Id name: type: string title: Name description: anyOf: - type: string - type: 'null' title: Description is_public: type: boolean title: Is Public created_at: type: string format: date-time title: Created At type: object required: - id - name - is_public - created_at title: ModelSummary description: |- A model the caller can pick for a prediction job. `is_public` marks a shared base model; the rest are the org's own saved custom models. examples: - created_at: '2026-01-15T09:30:00Z' description: Cellpose-SAM generalist base model id: c0ffee00-1234-5678-9abc-def012345678 is_public: true name: cpsam ErrorResponse: properties: detail: type: string title: Detail examples: - Job with id 11111111-1111-1111-1111-111111111111 not found type: object required: - detail title: ErrorResponse description: |- The body returned for a handled error: a single human-readable ``detail`` string. securitySchemes: HTTPBearer: type: http scheme: bearer ````