> ## Documentation Index
> Fetch the complete documentation index at: https://docs.membrane.agency/llms.txt
> Use this file to discover all available pages before exploring further.

# Get Credentials from Connection Parameters

The `getCredentialsFromConnectionParameters` method transforms user-provided connection parameters into the credential format required for authentication.\
This method is useful when the format of credentials needed by the authentication mechanism differs from what users provide during connection setup or when you need to make additional requests to get/refresh credentials.

When using this method, you almost always should define the structure of the credentials this method returns in the `customCredentialsSchema` field of the connector definition.

## Implementation

This method is implemented in JavaScript:

```yaml theme={null}
# Connector definition: Exchange user-provided email/password for an API access token
getCredentialsFromConnectionParameters:
  type: javascript
  code: |
    export default async function getCredentialsFromConnectionParameters({
      connectionInput,
    }) {
      const { email, password } = connectionInput
      const response = await fetch('https://api.example.com/v1/get-token', {
        method: 'POST',
        headers: { 'Content-Type': 'application/json' },
        body: JSON.stringify({ email, password }),
      })
      const data = await response.json()
      const accessToken = data?.access_token

      if (!accessToken) {
        throw new Error('Failed to get access token')
      }

      return { accessToken }
    }
```

## Input

The method receives a context object with these properties:

| Property              | Description                                                |
| --------------------- | ---------------------------------------------------------- |
| `connectionInput`     | Parameters provided by the user during connection setup.   |
| `connectorParameters` | Parameters configured for the connector in your workspace. |

## Return Value

The method should return an object containing the credentials that will be added to the `credentials` stored in the [Connection](/docs/how-membrane-works/connections) object.