> ## Documentation Index
> Fetch the complete documentation index at: https://docs.slideless.ai/llms.txt
> Use this file to discover all available pages before exploring further.

# POST /setTokenVersionMode

> Pin a share token to a specific version or put it back on auto-follow-latest. Owner-only.

<Note>
  For most use cases, the [`slideless` CLI](/cli/overview) is easier. The CLI command is `slideless pin <presentationId> <tokenId> --to-version <N>` or `--latest`.
</Note>

## Endpoint

```
POST https://europe-west1-slideless-ai.cloudfunctions.net/setTokenVersionMode
```

## Auth

| Header          | Value                                                                 |
| --------------- | --------------------------------------------------------------------- |
| `Authorization` | `Bearer cko_…` (or `cka_…`) — must belong to the presentation's owner |
| `Content-Type`  | `application/json`                                                    |

Required scope: `presentations:write`.

## Request body

| Field            | Type   | Required | Description                                                   |
| ---------------- | ------ | -------- | ------------------------------------------------------------- |
| `presentationId` | string | yes      | Presentation the token belongs to                             |
| `tokenId`        | string | yes      | Token to change                                               |
| `versionMode`    | object | yes      | Either `{"type":"latest"}` or `{"type":"pinned","version":N}` |

**Pinning rules:**

* `version` must be a positive integer
* `version` must not exceed `currentVersion`
* The token must not be revoked

Example — pin:

```json theme={"theme":{"light":"github-light","dark":"github-dark"}}
{
  "presentationId": "0192f1c3-...",
  "tokenId": "0192f1c3-abcd-...",
  "versionMode": { "type": "pinned", "version": 3 }
}
```

Example — unpin (follow latest):

```json theme={"theme":{"light":"github-light","dark":"github-dark"}}
{
  "presentationId": "0192f1c3-...",
  "tokenId": "0192f1c3-abcd-...",
  "versionMode": { "type": "latest" }
}
```

## Response (200)

```json theme={"theme":{"light":"github-light","dark":"github-dark"}}
{
  "success": true,
  "data": {
    "success": true,
    "versionMode": { "type": "pinned", "version": 3 }
  }
}
```

## Errors

| Status | Code                | Cause                                                                    |
| ------ | ------------------- | ------------------------------------------------------------------------ |
| `400`  | `invalid-argument`  | Bad `versionMode` shape, `version` > `currentVersion`, or missing fields |
| `401`  | `unauthenticated`   | Missing/invalid API key                                                  |
| `403`  | `permission-denied` | Key lacks `presentations:write`, or not the presentation's owner         |
| `404`  | `not-found`         | `presentationId` or `tokenId` doesn't exist                              |
| `410`  | `revoked`           | Cannot modify a revoked token                                            |

## Concept reminder

Recipients cannot see past versions by URL manipulation — there is no `?v=N` query parameter. Pinning is how the owner decides what a specific recipient sees, and that decision can only narrow: a `latest` token sees the current version; a `pinned` token is frozen. See [Versioning](/concepts/versioning).

## Next

* **[CLI: slideless pin](/cli/commands#slideless-pin-shareid-tokenid)** — the terminal version.
* **[Versioning](/concepts/versioning)** — concept deep dive.
* **[GET /getSharedPresentationInfo](/api-reference/get-presentation)** — inspect every token's current `versionMode`.