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# List AaAnnotation items

GET https://{tenant_name}.benchling.com/api/v3/aa-sequence/{aa_sequence_id}/annotations/items

List AaAnnotation items.

Reference: https://docs.benchling.com/docs/api/benchling-api/aa-sequence/annotations-list

## Authentication

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

## Request

### Path parameters

- `aa_sequence_id` (string, required) — ID of the AaSequence.

### 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 AaAnnotation, optional)
- `nextToken` (string, optional)

## Errors

### 400 Aa Sequence Annotations 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 Aa Sequence Annotations 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 Aa Sequence Annotations 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 Aa Sequence Annotations 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 Aa Sequence Annotations 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

### AaAnnotation

Represents an annotated region on an amino acid sequence (AaSequence). Annotations mark functional domains, binding sites, post-translational modifications, engineered mutations, or other biologically significant features. Each annotation defines a start and end position (0-based, exclusive end), a name, optional type classification, display color, and descriptive notes. Annotations appear as visual overlays on the sequence viewer.

- `__typename` (string, optional)
- `aaSequence` (AaSequenceRef, optional) — AA sequence the annotation belongs to.
- `color` (string, optional) — Hex color when displaying the annotation.
- `end` (integer, optional) — 0-based exclusive end index.
- `id` (string, optional) — ID of the annotation.
- `name` (string, optional) — Name of the annotation.
- `notes` (string, optional) — Text notes on the annotation.
- `start` (integer, optional) — 0-based inclusive start index.
- `type` (string, optional, nullable) — Feature type of the annotation.

### GeneralErrorDetail

### TooManyRequestsErrorBodyDetail

### InternalServerErrorBodyDetail

### AaSequenceRef

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

## Examples

**Response**

```json
{
  "items": [
    {
      "__typename": "__typename",
      "color": "color",
      "end": 1,
      "id": "id",
      "name": "name",
      "notes": "notes",
      "start": 1,
      "type": "type"
    }
  ],
  "nextToken": "nextToken"
}
```

**SDK Code**

```python
import requests

url = "https://{tenant_name}.benchling.com/api/v3/aa-sequence/aa_sequence_id/annotations/items"

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

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

print(response.json())
```

```javascript
const url = 'https://{tenant_name}.benchling.com/api/v3/aa-sequence/aa_sequence_id/annotations/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);
}
```