UpdateExperiment - CloudWatch Evidently


Updates an Evidently experiment.

Don't use this operation to update an experiment's tag. Instead, use TagResource.

Request Syntax

PATCH /projects/project/experiments/experiment HTTP/1.1 Content-type: application/json { "description": "string", "metricGoals": [ { "desiredChange": "string", "metricDefinition": { "entityIdKey": "string", "eventPattern": "string", "name": "string", "unitLabel": "string", "valueKey": "string" } } ], "onlineAbConfig": { "controlTreatmentName": "string", "treatmentWeights": { "string" : number } }, "randomizationSalt": "string", "samplingRate": number, "treatments": [ { "description": "string", "feature": "string", "name": "string", "variation": "string" } ] }

URI Request Parameters

The request uses the following URI parameters.


The name of the experiment to update.

Length Constraints: Minimum length of 1. Maximum length of 127.

Pattern: ^[-a-zA-Z0-9._]*$

Required: Yes


The name or ARN of the project that contains the experiment that you want to update.

Length Constraints: Minimum length of 0. Maximum length of 2048.

Pattern: ([-a-zA-Z0-9._]*)|(arn:[^:]*:[^:]*:[^:]*:[^:]*:project/[-a-zA-Z0-9._]*)

Required: Yes

Request Body

The request accepts the following data in JSON format.


An optional description of the experiment.

Type: String

Length Constraints: Minimum length of 0. Maximum length of 160.

Pattern: .*

Required: No


An array of structures that defines the metrics used for the experiment, and whether a higher or lower value for each metric is the goal.

Type: Array of MetricGoalConfig objects

Array Members: Minimum number of 1 item. Maximum number of 3 items.

Required: No


A structure that contains the configuration of which variation o use as the "control" version. The "control" version is used for comparison with other variations. This structure also specifies how much experiment traffic is allocated to each variation.

Type: OnlineAbConfig object

Required: No


When Evidently assigns a particular user session to an experiment, it must use a randomization ID to determine which variation the user session is served. This randomization ID is a combination of the entity ID and randomizationSalt. If you omit randomizationSalt, Evidently uses the experiment name as the randomizationSalt.

Type: String

Length Constraints: Minimum length of 0. Maximum length of 127.

Pattern: .*

Required: No


The portion of the available audience that you want to allocate to this experiment, in thousandths of a percent. The available audience is the total audience minus the audience that you have allocated to overrides or current launches of this feature.

This is represented in thousandths of a percent. For example, specify 20,000 to allocate 20% of the available audience.

Type: Long

Valid Range: Minimum value of 0. Maximum value of 100000.

Required: No


An array of structures that define the variations being tested in the experiment.

Type: Array of TreatmentConfig objects

Array Members: Minimum number of 0 items. Maximum number of 5 items.

Required: No

Response Syntax

HTTP/1.1 200 Content-type: application/json { "experiment": { "arn": "string", "createdTime": number, "description": "string", "execution": { "endedTime": number, "startedTime": number }, "lastUpdatedTime": number, "metricGoals": [ { "desiredChange": "string", "metricDefinition": { "entityIdKey": "string", "eventPattern": "string", "name": "string", "unitLabel": "string", "valueKey": "string" } } ], "name": "string", "onlineAbDefinition": { "controlTreatmentName": "string", "treatmentWeights": { "string" : number } }, "project": "string", "randomizationSalt": "string", "samplingRate": number, "schedule": { "analysisCompleteTime": number }, "status": "string", "statusReason": "string", "tags": { "string" : "string" }, "treatments": [ { "description": "string", "featureVariations": { "string" : "string" }, "name": "string" } ], "type": "string" } }

Response Elements

If the action is successful, the service sends back an HTTP 200 response.

The following data is returned in JSON format by the service.


A structure containing the configuration details of the experiment that was updated.

Type: Experiment object


For information about the errors that are common to all actions, see Common Errors.


You do not have sufficient permissions to perform this action.

HTTP Status Code: 403


A resource was in an inconsistent state during an update or a deletion.

HTTP Status Code: 409


The request references a resource that does not exist.

HTTP Status Code: 404


The value of a parameter in the request caused an error.

HTTP Status Code: 400

See Also

For more information about using this API in one of the language-specific AWS SDKs, see the following: