---
title: "Close the current milestone version and open the next"
method: POST
path: "/projects/{project_id}/versions"
tags: ["project-versions"]
---

# Close the current milestone version and open the next

`POST /projects/{project_id}/versions`

Freeze or abandon the current milestone and open its successor.

Args:
    project_id: Project to advance.
    request: Reviewed summary, its revision token, and close options.
    auth: Authenticated caller.

Returns:
    The closed milestone and the newly opened one.

## Path parameters

- `project_id` string, uuid, required

## Request body

- VersionCreateRequest — Request body for closing the current milestone and opening the next.
  - `revision_token` string, required — Token from the preview whose summary the caller reviewed.
  - `carryover_summary` string, required — Reviewed (and possibly edited) narrative to store on the closing milestone.
  - `objective` string, nullable — Objective for the new milestone.
  - `abandon` boolean — Close without a champion. Required when the milestone has none.
  - `carry_dataset_ids` string[], nullable — Dataset versions to carry forward. Omit to carry every reference on the closing milestone.

## Response `200`

Successful Response

- VersionCreateResponse — The outcome of a milestone transition.
  - `closed` ProjectVersionResponse, required — A single project milestone.
    - `id` string, required
    - `project_id` string, required
    - `team_id` string, required
    - `version_number` integer, required
    - `status` 'current' | 'frozen' | 'abandoned', required — Lifecycle of a project milestone version (EDD section 9.1).
    - `objective` string, nullable, required
    - `carryover_summary` string, required
    - `champion` ChampionRef, required — What a milestone settled on, as exactly one populated target.
      - `training_job_id` string, nullable — Fine-tune chosen as champion.
      - `base_model` string, nullable — Catalog base model chosen as champion.
    - `created_by` string, required
    - `closed_by` string, nullable, required
    - `closed_at` string, date-time, nullable, required
    - `created_at` string, date-time, required
  - `current` ProjectVersionResponse, required — A single project milestone.
    - `id` string, required
    - `project_id` string, required
    - `team_id` string, required
    - `version_number` integer, required
    - `status` 'current' | 'frozen' | 'abandoned', required — Lifecycle of a project milestone version (EDD section 9.1).
    - `objective` string, nullable, required
    - `carryover_summary` string, required
    - `champion` ChampionRef, required — What a milestone settled on, as exactly one populated target.
      - `training_job_id` string, nullable — Fine-tune chosen as champion.
      - `base_model` string, nullable — Catalog base model chosen as champion.
    - `created_by` string, required
    - `closed_by` string, nullable, required
    - `closed_at` string, date-time, nullable, required
    - `created_at` string, date-time, required

## Other responses

- `422` — Validation Error

---

[API](https://skmtc.net/pioneer/apis/brain-api.md) · [All operations](https://skmtc.net/pioneer/apis/brain-api/llms.txt) · [OpenAPI document](https://skmtc-service-staging.skmtc.workers.dev/v1/apis/pioneer/brain-api/revisions/b92f75fd3b61/schema)