---
title: "GET /v1/projects/{projectsId}/locations/{locationsId}/studies/{studiesId}/trials"
method: GET
path: "/v1/projects/{projectsId}/locations/{locationsId}/studies/{studiesId}/trials"
tags: ["projects"]
---

# GET /v1/projects/{projectsId}/locations/{locationsId}/studies/{studiesId}/trials

`GET /v1/projects/{projectsId}/locations/{locationsId}/studies/{studiesId}/trials`

## Request

- Base URL: `https://aiplatform.googleapis.com`
- URL: `https://aiplatform.googleapis.com/v1/projects/{projectsId}/locations/{locationsId}/studies/{studiesId}/trials`
- Auth: OAuth 2 and OAuth 2
  - Implicit: `https://accounts.google.com/o/oauth2/auth`
  - Scopes: `https://www.googleapis.com/auth/cloud-platform`
  - Authorization code: `https://accounts.google.com/o/oauth2/auth`
  - Token URL: `https://accounts.google.com/o/oauth2/token` scopes: `https://www.googleapis.com/auth/cloud-platform`

Lists the Trials associated with a Study.

## Path parameters

- `projectsId` string, required
- `locationsId` string, required
- `studiesId` string, required

## Query parameters

- `pageSize` integer
- `pageToken` string

## Response `200`

Successful response

- GoogleCloudAiplatformV1ListTrialsResponse: Response message for VizierService.ListTrials.
  - `nextPageToken` string: Pass this token as the `page_token` field of the request for a subsequent call. If this field is omitted, there are no subsequent pages.
  - `trials` GoogleCloudAiplatformV1Trial[]: The Trials associated with the Study.
    - `clientId` string: Output only. The identifier of the client that originally requested this Trial. Each client is identified by a unique client_id. When a client asks for a suggestion, Vertex AI Vizier will assign it a Trial. The client should evaluate the Trial, complete it, and report back to Vertex AI Vizier. If suggestion is asked again by same client_id before the Trial is completed, the same Trial will be returned. Multiple clients with different client_ids can ask for suggestions simultaneously, each of them will get their own Trial.
    - `customJob` string: Output only. The CustomJob name linked to the Trial. It's set for a HyperparameterTuningJob's Trial.
    - `endTime` string, google-datetime: Output only. Time when the Trial's status changed to `SUCCEEDED` or `INFEASIBLE`.
    - `finalMeasurement` GoogleCloudAiplatformV1Measurement: A message representing a Measurement of a Trial. A Measurement contains the Metrics got by executing a Trial using suggested hyperparameter values.
      - `elapsedDuration` string, google-duration: Output only. Time that the Trial has been running at the point of this Measurement.
      - `metrics` GoogleCloudAiplatformV1MeasurementMetric[]: Output only. A list of metrics got by evaluating the objective functions using suggested Parameter values.
        - `metricId` string: Output only. The ID of the Metric. The Metric should be defined in StudySpec's Metrics.
        - `value` number, double: Output only. The value for this metric.
      - `stepCount` string, int64: Output only. The number of steps the machine learning model has been trained for. Must be non-negative.
    - `id` string: Output only. The identifier of the Trial assigned by the service.
    - `infeasibleReason` string: Output only. A human readable string describing why the Trial is infeasible. This is set only if Trial state is `INFEASIBLE`.
    - `measurements` GoogleCloudAiplatformV1Measurement[]: Output only. A list of measurements that are strictly lexicographically ordered by their induced tuples (steps, elapsed_duration). These are used for early stopping computations.
      - `elapsedDuration` string, google-duration: Output only. Time that the Trial has been running at the point of this Measurement.
      - `metrics` GoogleCloudAiplatformV1MeasurementMetric[]: Output only. A list of metrics got by evaluating the objective functions using suggested Parameter values.
        - `metricId` string: Output only. The ID of the Metric. The Metric should be defined in StudySpec's Metrics.
        - `value` number, double: Output only. The value for this metric.
      - `stepCount` string, int64: Output only. The number of steps the machine learning model has been trained for. Must be non-negative.
    - `name` string: Output only. Resource name of the Trial assigned by the service.
    - `parameters` GoogleCloudAiplatformV1TrialParameter[]: Output only. The parameters of the Trial.
      - `parameterId` string: Output only. The ID of the parameter. The parameter should be defined in StudySpec's Parameters.
      - `value` unknown
    - `startTime` string, google-datetime: Output only. Time when the Trial was started.
    - `state` 'STATE_UNSPECIFIED' | 'REQUESTED' | 'ACTIVE' | 'STOPPING' | 'SUCCEEDED' | 'INFEASIBLE': Output only. The detailed state of the Trial.
    - `webAccessUris` object: Output only. URIs for accessing [interactive shells](https://cloud.google.com/vertex-ai/docs/training/monitor-debug-interactive-shell) (one URI for each training node). Only available if this trial is part of a HyperparameterTuningJob and the job's trial_job_spec.enable_web_access field is `true`. The keys are names of each node used for the trial; for example, `workerpool0-0` for the primary node, `workerpool1-0` for the first node in the second worker pool, and `workerpool1-1` for the second node in the second worker pool. The values are the URIs for each node's interactive shell.

---

[API](https://skmtc.dev/google/apis/aiplatform.md) - [All operations](https://skmtc.dev/google/apis/aiplatform/llms.txt) - [OpenAPI document](https://skmtc.dev/google/apis/aiplatform/revisions/3aca3b348f0c?raw)