<!-- source: https://secondlayer.tools/docs/api-reference#subgraph-gap-object -->

## The Subgraph gap object

A block range the subgraph did not process.

| Field | Type | Description |
| --- | --- | --- |
| `start` | integer | First missing block. |
| `end` | integer | Last missing block, inclusive. |
| `size` | integer | Blocks in the range. |
| `reason` | enum | `block_missing`: the block was not in the index. `processing_error`: a handler threw. Values: `block_missing`, `processing_error`. |
| `detectedAt` | string · date-time | When it was recorded. |
| `resolvedAt` | string · date-time · nullable | When a later walk covered it. `null` while open. |

```json
{
  "start": 8412207,
  "end": 8412207,
  "size": 1,
  "reason": "processing_error",
  "detectedAt": "2026-09-22T18:40:03.000Z",
  "resolvedAt": null
}
```