# Single

The order book endpoint provides an order book's bids and asks and can be used in [streaming](/api/introduction/streaming.md) mode.

When filtering for a specific order book, you must use use all six of these arguments: `base_asset_type`, `base_asset_issuer`, `base_asset_code`, `counter_asset_type`, `counter_asset_issuer`, and `counter_asset_code`. If the base or counter asset is XLM, you only need to indicate the asset type as `native` and do not need to designate the code or the issuer.

 \- ARGUMENT - 

* selling\_asset\_type `required`

  The type for the asset being sold (base asset). Either `native`, `credit_alphanum4`, or `credit_alphanum12`.
* selling\_asset\_issuer `optional`

  The Stellar address of the issuer of the asset being sold (base asset). Required if the `selling_asset_type` is not `native`.
* selling\_asset\_code `optional`

  The code for the asset being sold (base asset). Required if the `selling_asset_type` is not `native`.
* buying\_asset\_type `required`

  The type for the asset being bought (counter asset). Either `native`, `credit_alphanum4`, or `credit_alphanum12`.
* buying\_asset\_issuer `optional`

  The Stellar address of the issuer of the asset being bought (counter asset). Required if the `buying_asset_type` is not `native`.
* buying\_asset\_code `optional`

  The code for the asset being bought (counter asset). Required if the `buying_asset_type` is not `native`.
* limit `optional`

  The total number of records returned. The limit can range from 1 to 200—an upper limit that is hardcoded in Horizon for performance reasons. If this argument isn’t designated, it defaults to 20 for order books.

{% tabs %}
{% tab title="JavaScript" %}

```javascript
var StellarSdk = require("stellar-sdk");
var server = new StellarSdk.Server("https://expansion-testnet.bantu.network");

server
  .orderbook(
    new StellarSdk.Asset.native(),
    new StellarSdk.Asset(
      "BB1",
      "GD5J6HLF5666X4AZLTFTXLY46J5SW7EXRKBLEYPJP33S33MXZGV6CWFN",
    ),
  )
  .call()
  .then(function (resp) {
    console.log(resp);
  })
  .catch(function (err) {
    console.error(err);
  });
```

{% endtab %}

{% tab title="cURL" %}

```bash
curl "https://expansion-testnet.bantu.network/order_book?selling_asset_type=native&buying_asset_type=credit_alphanum4&buying_asset_code=BB1&buying_asset_issuer=GD5J6HLF5666X4AZLTFTXLY46J5SW7EXRKBLEYPJP33S33MXZGV6CWFN&limit=4"
```

{% endtab %}
{% endtabs %}

{% code title="Example Response" %}

```bash
{
  "bids": [
    {
      "price_r": {
        "n": 10000000,
        "d": 139999999
      },
      "price": "0.0714286",
      "amount": "24.9999990"
    },
    {
      "price_r": {
        "n": 1,
        "d": 14
      },
      "price": "0.0714286",
      "amount": "188.0000000"
    },
    {
      "price_r": {
        "n": 1,
        "d": 15
      },
      "price": "0.0666667",
      "amount": "230.3200000"
    },
    {
      "price_r": {
        "n": 1,
        "d": 16
      },
      "price": "0.0625000",
      "amount": "50.0000000"
    }
  ],
  "asks": [
    {
      "price_r": {
        "n": 5000000,
        "d": 62500001
      },
      "price": "0.0800000",
      "amount": "4.9400001"
    },
    {
      "price_r": {
        "n": 10000000,
        "d": 125000001
      },
      "price": "0.0800000",
      "amount": "2516.5154327"
    },
    {
      "price_r": {
        "n": 2,
        "d": 25
      },
      "price": "0.0800000",
      "amount": "3125.0000000"
    },
    {
      "price_r": {
        "n": 4,
        "d": 49
      },
      "price": "0.0816327",
      "amount": "4593.7500000"
    }
  ],
  "base": {
    "asset_type": "native"
  },
  "counter": {
    "asset_type": "credit_alphanum4",
    "asset_code": "BB1",
    "asset_issuer": "GD5J6HLF5666X4AZLTFTXLY46J5SW7EXRKBLEYPJP33S33MXZGV6CWFN"
  }
}
```

{% endcode %}

```javascript
var StellarSdk = require("stellar-sdk");
var server = new StellarSdk.Server("https://expansion-testnet.bantu.network");

var callback = function (resp) {
  console.log(resp);
};

var es = server
  .orderbook(
    new StellarSdk.Asset.native(),
    new StellarSdk.Asset(
      "BB1",
      "GD5J6HLF5666X4AZLTFTXLY46J5SW7EXRKBLEYPJP33S33MXZGV6CWFN",
    ),
  )
  .cursor("now")
  .stream({ onmessage: callback });
```


---

# Agent Instructions: Querying This Documentation

If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question.

Perform an HTTP GET request on the current page URL with the `ask` query parameter:

```
GET https://developers.docs.bantufoundation.org/api/aggregations/order-books/single.md?ask=<question>
```

The question should be specific, self-contained, and written in natural language.
The response will contain a direct answer to the question and relevant excerpts and sources from the documentation.

Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.