# Change a supply exchange rate

This method allows a TEOS user to update the exchange rate of an existing supply. Supply represents an offer created by a user to trade a specific amount of one asset for a specific amount of another asset. By changing the exchange rate, the user can adjust the amount of desired asset received per unit of offered asset for that supply.

📘[ Learn more ](/resources/using-the-teos-api/concepts/supply.md)about supplies.

#### Request Endpoint:

```http
POST
/odata/v1.0/Supplies({key})/ChangeExchangeRate
```

#### Parameters

| **Name** | **Description**                                                                                                                            |
| -------- | ------------------------------------------------------------------------------------------------------------------------------------------ |
| key      | string (path) — The unique identifier of the supply to update. Example: 0x1EAEFD42D684567ABDC7000193A96C4653DE1314DB20000167242CB20000024E |

#### Request Body

`application/json` 

| **Field**    | **Type** | **Description**                                                                                              |
| ------------ | -------- | ------------------------------------------------------------------------------------------------------------ |
| exchangeRate | string   | The new exchange rate for the supply, representing the amount of desired asset per 1 spark of offered asset. |

#### Example Request

```http
POST /Supplies('0x1EAEFD42D684567ABDC7000193A96C4653DE1314DB20000167242CB20000024E')/ChangeExchangeRate
```

**Content-Type:** `application/json` 

```json
{
  "exchangeRate": "1"
}
```

#### Example Response Body

```json
{
  "Id": "C0D34D73-6FD3-40F2-A7E1-08D9412448F7",
  "State": "3",
  "BlockchainTransactionId": "0x748ac47e7226cae0e4e13373375f33ab9e4d43ef29d85d233162a7e7e913703b",
  "CorrelationId": "3fa85f64-5717-4562-b3fc-2c963f66afa6",
  "Type": "ActivateAsset",
  "OnCreated": "2025-10-08T09:36:47.978Z",
  "OnUpdated": "2025-10-08T09:36:47.978Z",
  "OnSubmitted": "2025-10-08T09:36:47.978Z",
  "OnCommitted": "2025-10-08T09:36:47.978Z",
  "OnConfirmed": "2025-10-08T09:36:47.978Z",
  "OnRevokedByBlockchain": "2025-10-08T09:36:47.978Z",
  "OnRevokedByUser": "2025-10-08T09:36:47.978Z",
  "OnRevokedByTxServer": "2025-10-08T09:36:47.978Z",
  "SignedBy": "string",
  "CreatedBy": "3fa85f64-5717-4562-b3fc-2c963f66afa6",
  "GasPrice": "string",
  "GasUsed": "string",
  "DataAsJson": "string",
  "SigningParametersAsJson": "string"
}
```

#### Response Body Fields Description

| **Field**               | **Type** | **Description**                                                 |
| ----------------------- | -------- | --------------------------------------------------------------- |
| Id                      | string   | Transaction ID of the exchange rate update.                     |
| State                   | string   | Current state of the transaction.                               |
| BlockchainTransactionId | string   | ID of the transaction on blockchain.                            |
| CorrelationId           | string   | Correlation ID for tracking the transaction.                    |
| Type                    | string   | Type of the transaction.                                        |
| OnCreated               | datetime | Timestamp when the transaction was created.                     |
| OnUpdated               | datetime | Timestamp when the transaction was last updated.                |
| OnSubmitted             | datetime | Timestamp when the transaction was submitted.                   |
| OnCommitted             | datetime | Timestamp when the transaction was committed.                   |
| OnConfirmed             | datetime | Timestamp when the transaction was confirmed.                   |
| OnRevokedByBlockchain   | datetime | Timestamp if the transaction was revoked by blockchain.         |
| OnRevokedByUser         | datetime | Timestamp if the transaction was revoked by user.               |
| OnRevokedByTxServer     | datetime | Timestamp if the transaction was revoked by transaction server. |
| SignedBy                | string   | Identifier of the signer.                                       |
| CreatedBy               | string   | Identifier of the creator.                                      |
| GasPrice                | string   | Gas price used in the transaction.                              |
| GasUsed                 | string   | Gas used by the transaction.                                    |
| DataAsJson              | string   | Additional transaction data in JSON.                            |
| SigningParametersAsJson | string   | Parameters used for signing the transaction.                    |

#### Responses

| **Code** | **Description**                                                         |
| -------- | ----------------------------------------------------------------------- |
| 201      | The transaction was successfully created.                               |
| 202      | Accepted. The exchange rate change transaction has been submitted.      |
| 400      | The supplied exchange rate data is invalid. Error details are included. |
| 401      | Unauthorized.                                                           |

<br>


---

# 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://teos-docs.coreledger.net/guides/supplies/change-a-supply-exchange-rate.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.