List test cohorts

Deprecated. This page documents the v2 buyer API, which is closed to new API clients and switches off on 1 December 2026. Use V3 instead: see Move a v2 buyer REST integration to V3. The conversion endpoint, Log event, stays open.

GET /api/v2/buyer/advertisers/{advertiserId}/test-cohorts Lists test cohorts for an advertiser — the treatment, control, and observation arms used in incrementality tests. Filter by role and active status.

Request

curl "https://api.apostra.com/api/v2/buyer/advertisers/12345/test-cohorts?role=TREATMENT&isActive=true&take=50&skip=0" \
  -H "Authorization: Bearer $SCOPE3_API_KEY"

Parameters

Field	Type	Required	Notes
`advertiserId`	string	Yes	Path parameter — the owning advertiser
`role`	enum	No	`TREATMENT`, `CONTROL`, or `OBSERVATION`
`isActive`	boolean	No	Filter by active status
`take`	integer	No	Page size, max 250 (default 50)
`skip`	integer	No	Offset for pagination (default 0)

Response

{
  "cohorts": [
    {
      "id": "cohort_abc123",
      "advertiserId": "12345",
      "name": "West Coast Treatment Group",
      "cohortType": "geographic",
      "role": "TREATMENT",
      "estimatedSize": 50000,
      "isActive": true,
      "createdAt": "2026-01-15T10:30:00Z",
      "updatedAt": "2026-01-20T14:45:00Z"
    }
  ],
  "total": 6
}

Returns compact cohort summaries plus a total count matching the query. Summaries omit definition and description — use Get test cohort for the full resource. This endpoint is offset-paginated; see Pagination for the meta.pagination envelope fields.

Errors

404 NOT_FOUND — advertiserId does not exist or is not visible to the authenticated account.

See Errors for the full error contract.

Measurement tasks

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Create test cohort

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Core Concepts

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Cross-Cutting Reference

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Release Notes

List test cohorts

Request

Parameters

Response

Errors

Measurement tasks

Measurement overview

Create test cohort

​Request

​Parameters

​Response

​Errors

​Related

Measurement tasks

Measurement overview

Create test cohort

Request

Parameters

Response

Errors

Related