---
title: "Save a draft with optimistic concurrency"
method: PATCH
path: "/v1/canvases/{canvasId}"
tags: ["Canvases"]
---

# Save a draft with optimistic concurrency

`PATCH /v1/canvases/{canvasId}`

## Request

- Base URL: `https://api.masko.ai`
- URL: `https://api.masko.ai/v1/canvases/{canvasId}`
- Auth: HTTP bearer

Replaces the whole graph. Send the latest `graph_content_hash` as `expected_graph_hash`; if the canvas changed since you read it, the request returns 409 and you should read it again.

## Path parameters

- `canvasId` string, uuid, required

## Request body

- object
  - `graph` object, required
  - `expected_graph_hash` string, required

## Response `200`

Successful response

- object
  - `data` object, required
    - `object` 'canvas', required
    - `id` string, uuid, required
    - `project_id` string, uuid, nullable, required
    - `mascot_id` string, uuid, nullable, required
    - `name` string, required
    - `graph` object, nullable, required
    - `graph_content_hash` string, required
    - `created_at` string, nullable, required
    - `updated_at` string, nullable, required

## Other responses

- `400`: Invalid input
- `401`: Authentication required
- `403`: Write key required
- `404`: Resource not found in credential workspace
- `409`: Revision conflict or retained history
- `422`: Required release media unavailable

---

[API](https://skmtc.dev/masko/apis/masko-api.md) · [All operations](https://skmtc.dev/masko/apis/masko-api/llms.txt) · [OpenAPI document](https://skmtc.dev/masko/apis/masko-api/revisions/84832e255613?raw)