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# List DnaPart items

GET https://{tenant_name}.benchling.com/api/v3/dna-sequence/{dna_sequence_id}/parts/items

List DnaPart items.

Reference: https://docs.benchling.com/docs/api/benchling-api/dna-sequence/parts-list

## Authentication

- `Authorization` header (bearer token, required) — Bearer authentication of the form `Bearer <token>`, where token is your auth token.

## Request

### Path parameters

- `dna_sequence_id` (string, required) — ID of the DnaSequence.

### Query parameters

- `nextToken` (string, optional) — Token for pagination
- `pageSize` (integer, optional) — Number of results to return. Defaults to 50, maximum of 100.

## Response

### 200

OK

- `items` (list of DnaPart, optional)
- `nextToken` (string, optional)

## Errors

### 400 Dna Sequence Parts List Request Bad Request Error

Bad Request

- `detail` (GeneralErrorDetail, required, nullable)
- `instance` (string, required)
- `status` (integer, required)
- `title` (string, required, nullable)
- `type` (string, required)
- `invalidId` (string, optional)

### 403 Dna Sequence Parts List Request Forbidden Error

Forbidden

- `detail` (GeneralErrorDetail, required, nullable)
- `instance` (string, required)
- `status` (integer, required)
- `title` (string, required, nullable)
- `type` (string, required)
- `invalidId` (string, optional)

### 404 Dna Sequence Parts List Request Not Found Error

Not Found

- `detail` (GeneralErrorDetail, required, nullable)
- `instance` (string, required)
- `status` (integer, required)
- `title` (string, required, nullable)
- `type` (string, required)
- `invalidId` (string, optional)

### 429 Dna Sequence Parts List Request Too Many Requests Error

Too Many Requests

- `detail` (TooManyRequestsErrorBodyDetail, required, nullable)
- `instance` (string, required)
- `status` (integer, required)
- `title` (string, required, nullable)
- `type` (string, required)
- `invalidId` (string, optional)
- `violated-policies` (list of enum, optional) — The budget policies that rejected the request, in canonical order: `user`, `integration`, then `tenant`.
  - Allowed values: `user`, `integration`, `tenant`

### 500 Dna Sequence Parts List Request Internal Server Error

Internal Server Error

- `detail` (InternalServerErrorBodyDetail, required, nullable)
- `instance` (string, required)
- `status` (integer, required)
- `title` (string, required, nullable)
- `type` (string, required)
- `errorId` (string, optional)

## Types

### DnaPart

Represents a region on a DNA sequence that matches or is derived from another registered DNA sequence. DnaPart features enable tracking the provenance of sequence regions, such as identifying that a particular gene in a construct originates from a specific source sequence. Each part specifies the referenced DnaSequence, the strand orientation (forward or reverse), and the position range using 0-based coordinates with an exclusive end index. Parts appear as visual features on the sequence viewer and support traceability from assembled constructs back to their component sequences.

- `__typename` (string, optional)
- `containerSequence` (DnaSequenceRef, optional) — The DNA sequence that contains this part.
- `end` (integer, optional) — 0-based exclusive end index. For ranges ending at the end of a circular sequence, this value is always the length of the sequence, never 0.
- `id` (string, optional) — The ID of the DNA Part.
- `sequence` (DnaSequenceRef, optional) — DNA sequence this part refers to.
- `start` (integer, optional) — 0-based inclusive start index.
- `strand` (enum, optional) — Strand orientation for this part: `FORWARD` or `REVERSE`.
  - Allowed values: `FORWARD`, `REVERSE`

### GeneralErrorDetail

### TooManyRequestsErrorBodyDetail

### InternalServerErrorBodyDetail

### DnaSequenceRef

- `__typename` (string, optional)
- `id` (string, optional)

## Examples

**Response**

```json
{
  "items": [
    {
      "__typename": "__typename",
      "end": 1,
      "id": "id",
      "start": 1,
      "strand": "FORWARD"
    }
  ],
  "nextToken": "nextToken"
}
```

**SDK Code**

```python
import requests

url = "https://{tenant_name}.benchling.com/api/v3/dna-sequence/dna_sequence_id/parts/items"

headers = {"Authorization": "Bearer <token>"}

response = requests.get(url, headers=headers)

print(response.json())
```

```javascript
const url = 'https://{tenant_name}.benchling.com/api/v3/dna-sequence/dna_sequence_id/parts/items';
const options = {method: 'GET', headers: {Authorization: 'Bearer <token>'}};

try {
  const response = await fetch(url, options);
  const data = await response.json();
  console.log(data);
} catch (error) {
  console.error(error);
}
```