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# List AaMonomer items

GET https://{tenant_name}.benchling.com/api/v3/aa-monomer/items

List AaMonomer items.

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

## Authentication

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

## Request

### Query parameters

- `archiveReason.anyOf` (string, optional) — Restricts items to those with any of the specified archive reasons. Use "NOT_ARCHIVED" to filter for unarchived items. Use "ANY_ARCHIVED" to filter for archived items regardless of reason. Use "ANY_ARCHIVED_OR_NOT_ARCHIVED" to return items for both archived and unarchived. Comma-separated list.
- `archived.anyOf` (boolean, optional) — If true, returns archived items. If false, returns unarchived items. If both true and false, returns archived and unarchived items. Comma-separated list.
- `createdAt.gt` (string, optional) — Datetime, in RFC 3339 format. Time zone defaults to UTC. Restricts results to those created after the specified time. e.g. > 2017-04-30.
- `createdAt.gte` (string, optional) — Datetime, in RFC 3339 format. Time zone defaults to UTC. Restricts results to those created at or after the specified time. e.g. >= 2017-04-30.
- `createdAt.lt` (string, optional) — Datetime, in RFC 3339 format. Time zone defaults to UTC. Restricts results to those created before the specified time. e.g. \< 2017-04-30.
- `createdAt.lte` (string, optional) — Datetime, in RFC 3339 format. Time zone defaults to UTC. Restricts results to those created at or before the specified time. e.g. \<= 2017-04-30.
- `id.anyOf` (string, optional) — Restricts results to those matching any of the specified IDs. Comma-separated list.
- `modifiedAt.gt` (string, optional) — Datetime, in RFC 3339 format. Time zone defaults to UTC. Restricts results to those modified after the specified time. e.g. > 2017-04-30.
- `modifiedAt.gte` (string, optional) — Datetime, in RFC 3339 format. Time zone defaults to UTC. Restricts results to those modified at or after the specified time. e.g. >= 2017-04-30.
- `modifiedAt.lt` (string, optional) — Datetime, in RFC 3339 format. Time zone defaults to UTC. Restricts results to those modified before the specified time. e.g. \< 2017-04-30.
- `modifiedAt.lte` (string, optional) — Datetime, in RFC 3339 format. Time zone defaults to UTC. Restricts results to those modified at or before the specified time. e.g. \<= 2017-04-30.
- `name.anyOf` (string, optional) — Restricts results to those that match any of the specified names. Case insensitive. Warning - this filter can be non-performant due to case insensitivity. Ensure only one name filter is used at a time. Comma-separated list.
- `name.anyOf.caseSensitive` (string, optional) — Restricts results to those that match any of the specified names. Case sensitive. Ensure only one name filter is used at a time. Comma-separated list.
- `nextToken` (string, optional) — Token for pagination
- `omit` (string, optional) — Comma-separated list of top-level fields to omit from each returned item. Cannot overlap with returning.
- `pageSize` (integer, optional) — Number of results to return. Defaults to 50, maximum of 100.
- `returning` (string, optional) — Comma-separated list of top-level fields to include in each returned item. Cannot overlap with omit.
- `sort` (enum, optional, default: modifiedAt:desc) — Method by which to order results. Valid sorts are: createdAt (created time, oldest first) and modifiedAt (modified time, oldest first). Use :asc or :desc to specify ascending or descending order. Default is modifiedAt:desc.
  - Allowed values: `createdAt:asc`, `createdAt:desc`, `modifiedAt:asc`, `modifiedAt:desc`

### Headers

- `EARLY-ACCESS` (string, optional) — Set to true to access beta operations via /api/v3.

## Response

### 200

OK

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

## Errors

### 400 Aa Monomer 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 Monomer 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 Monomer 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 Monomer 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 Monomer 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

### AaMonomer

An amino acid monomer is a building block for modified peptide sequences. Each AA monomer has a symbol identifier, chemical structure (SMILES/molfile), molecular weight, and attachment points defining where it bonds to other monomers. The naturalAnalog field links modified monomers to their standard amino acid counterpart (e.g., a modified alanine analog links to natural 'A'). AA monomers define the chemistry of non-standard amino acids used in peptide and protein engineering.

- `__typename` (string, optional)
- `archiveReason` (string, optional, nullable)
- `archived` (boolean, optional)
- `attachmentPoints` (list of enum, optional) — The capping groups present at each attachment point where the monomer bonds to other monomers.
  - Allowed values: `H`, `OH`, `NH2`, `CH3`
- `calculatedMolecularWeight` (double, optional) — The molecular weight of the monomer with capping groups removed, computed using the average atomic weights of each element weighted by natural isotopic frequency.
- `canonicalSmiles` (string, optional) — The SMILES representation of the chemical structure after being standardized.
- `createdAt` (string, optional)
- `creator` (PrincipalRef, optional, nullable)
- `customMolecularWeight` (double, optional, nullable) — Optional molecular weight value that the user can provide to override the calculated value.
- `exactMolecularWeight` (double, optional) — The exact (monoisotopic) molecular weight of the monomer with capping groups removed, computed using the atomic weight of the most frequent isotope of each element.
- `id` (string, optional)
- `isNatural` (boolean, optional) — Whether this monomer represents a natural (unmodified) amino acid, as opposed to a modified or synthetic variant.
- `modifiedAt` (string, optional)
- `molfile` (string, optional) — The molfile representation of the chemical structure.
- `name` (string, optional)
- `naturalAnalog` (enum, optional) — The standard amino acid single-letter code that this monomer is an analog of.
  - Allowed values: `A`, `B`, `C`, `D`, `E`, `F`, `G`, `H`, `I`, `J`, `K`, `L`, `M`, `N`, `O`, `P`, `Q`, `R`, `S`, `T`, `U`, `V`, `W`, `X`, `Y`, `Z`
- `originalSmiles` (string, optional, nullable) — The SMILES string that was originally provided upon creation. Null if the user did not originally provide SMILES.
- `symbol` (string, optional) — User-defined identifier of the monomer, unique per tenant.

### GeneralErrorDetail

### TooManyRequestsErrorBodyDetail

### InternalServerErrorBodyDetail

### PrincipalRef

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

## Examples

**Response**

```json
{
  "items": [
    {
      "__typename": "__typename",
      "archiveReason": "archiveReason",
      "archived": true,
      "attachmentPoints": [
        "H"
      ],
      "calculatedMolecularWeight": 1.1,
      "canonicalSmiles": "canonicalSmiles",
      "createdAt": "createdAt",
      "customMolecularWeight": 1.1,
      "exactMolecularWeight": 1.1,
      "id": "id",
      "isNatural": true,
      "modifiedAt": "modifiedAt",
      "molfile": "molfile",
      "name": "name",
      "naturalAnalog": "A",
      "originalSmiles": "originalSmiles",
      "symbol": "symbol"
    }
  ],
  "nextToken": "nextToken"
}
```

**SDK Code**

```python
import requests

url = "https://{tenant_name}.benchling.com/api/v3/aa-monomer/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-monomer/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);
}
```