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

# Get Session Graph Element

Fetch a single element from a graph session object by id.

## **POST** `/revisions/:id/data/query` (Command: `get_session_graph_element`)

### Request Body

| Parameter    | Type   | Required | Description                                         |
| :----------- | :----- | :------- | :-------------------------------------------------- |
| `engine`     | string | Yes      | Must be `workflow_blobhub`.                         |
| `command`    | string | Yes      | Must be `get_session_graph_element`.                |
| `session_id` | string | Yes      | The ID of the session that owns the graph envelope. |
| `alias`      | string | Yes      | Alias of the graph session object.                  |
| `element_id` | string | Yes      | The id of the vertex or edge to retrieve.           |

### Response

| Parameter | Type   | Description                   |
| :-------- | :----- | :---------------------------- |
| `element` | object | The retrieved vertex or edge. |

### Errors

* `invalid_graph_envelope` — the alias does not exist or its `value.type` is not `"graph"`.
* `not_found` (404) — no element with that `element_id` exists in the graph.

### Example

<CodeGroup>
  ```json Request theme={null}
  {
    "engine": "workflow_blobhub",
    "command": "get_session_graph_element",
    "session_id": "sess_001",
    "alias": "task_graph",
    "element_id": "task:1"
  }
  ```

  ```json Response theme={null}
  {
    "element": {
      "element_id": "task:1",
      "type": "vertex",
      "labels": ["task"],
      "props": { "title": "Research", "status": "in_progress" },
      "rev": 2,
      "created_at": "2026-06-06T10:00:00.000000+00:00",
      "updated_at": "2026-06-06T10:00:01.000000+00:00",
      "user_id": "usr_001"
    }
  }
  ```
</CodeGroup>

### See also

* [Graph session object](/blob-types/workflow/session-objects/graph/introduction) — envelope shape and element schema.
* [Apply Session Graph Mutations](/blob-types/workflow/operations/apply-session-graph-mutations) — write vertices and edges.
* [Get Session Graph Elements](/blob-types/workflow/operations/get-session-graph-elements) — fetch multiple elements by id in one call.
* [List Session Graph Elements](/blob-types/workflow/operations/list-session-graph-elements) — paginate all elements.
* [List Session Graph Neighbors](/blob-types/workflow/operations/list-session-graph-neighbors) — fetch neighbors of a set of vertices.
* [Query Session Graph](/blob-types/workflow/operations/query-session-graph) — traverse the graph with a query AST.