---
title: "Preview closing the current milestone version"
method: GET
path: "/projects/{project_id}/versions/preview-close"
tags: ["project-versions"]
---

# Preview closing the current milestone version

`GET /projects/{project_id}/versions/preview-close`

Describe what closing the current milestone would record, writing nothing.

Args:
    project_id: Project to read.
    auth: Authenticated caller.

Returns:
    The manifest, a reviewable summary, any blockers, and the revision token.

## Path parameters

- `project_id` string, uuid, required

## Response `200`

Successful Response

- VersionPreviewResponse — What closing the current milestone would record.
  - `version_id` string, required — Milestone this preview describes.
  - `version_number` integer, required
  - `manifest` CarryoverManifestPayload, required — Deterministic snapshot of a milestone's contents.
    - `schema_version` integer, required — Manifest shape version.
    - `version` ManifestVersionRef, required — Identity of the milestone a manifest describes.
      - `id` string, required — Milestone UUID.
      - `number` integer, required — Monotonic per-project version number.
      - `objective` string, nullable — Goal set when the version opened.
    - `training_jobs` ManifestTrainingJob[]
      - `id` string, required — Training job UUID.
      - `model_name` string, nullable — Customer-facing model name.
      - `version_number` string, required — Version within the model lineage.
      - `base_model` string, required — Base model it was trained from.
      - `status` string, required — Raw persisted training status.
      - `deployable` boolean, required — Whether the artifact may serve traffic.
      - `not_deployable_reason` string, nullable — Stable reason code when the artifact cannot serve traffic.
    - `datasets` ManifestDataset[]
      - `id` string, required — Dataset UUID; an exact immutable version.
      - `name` string, required — Dataset name.
      - `version_number` string, required — Version within the dataset lineage.
    - `experiments` ManifestExperiment[]
      - `id` string, required — Experiment UUID.
      - `title` string, nullable — Agent-generated display name.
      - `stage` 'scoping' | 'preparing_data' | 'training' | 'evaluating' | 'complete' | 'blocked' | 'cancelled', required — Agent-owned workflow stage of an Experiment (EDD section 0.2).
    - `champion` ChampionRef — 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.
  - `summary` string, required — Reviewable narrative carryover; the rendered manifest when the agent could not produce one.
  - `summary_is_fallback` boolean, required — True when the narrative agent failed and the deterministic rendering was used.
  - `revision_token` string, required — Hash of the manifest; required by the create call.
  - `champion` ChampionRef — 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.
  - `blockers` ActiveWorkBlockerResponse[] — Unfinished work that must terminate before this milestone can close.
    - `kind` string, required — Blocking resource type: training_job or experiment.
    - `resource_id` string, required — Identifier of the blocking row.
    - `label` string, required — Customer-safe name of the blocking row.
    - `detail` string, required — Why it blocks the transition.
  - `can_close` boolean, required — Whether a create call would be accepted right now.
  - `carry_dataset_ids` string[] — Dataset versions that would be carried into the next milestone by default.

## 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)