> For the complete documentation index, see [llms.txt](https://fusionauth.io/docs/llms.txt)

# Error Codes

Learn about the error response that is returned from FusionAuth APIs.

When FusionAuth encounters an error or finds validation errors in your request, an Errors object is returned in the response body. The Errors object is defined as follows, where **fieldName** indicates the field in the request body the message is describing and **\[x\]** indicates the value is part of an array of one or more values.

## Error Fields

`generalErrors`

*   Array

The list of general error messages.

`generalErrors[x].code`

*   String

The code of the error message.

`generalErrors[x].message`

*   String

A descriptive error message that details the problem that occurred.

`fieldErrors`

*   Object

The list of field error message.

`fieldErrors[fieldName]`

*   Array

The list of error messages for that field

`fieldErrors[fieldName][x].code`

*   String

The code of the error message.

`fieldErrors[fieldName][x].message`

*   String

A descriptive error message that details the problem that occurred.

*Example Errors JSON Object*

```json
{
  "generalErrors": [
    {
      "code": "[invalid]",
      "message": "Your JSON was invalid"
    }
  ],
  "fieldErrors": {
    "user.username": [
      {
        "code": "[duplicate]user.username",
        "message": "A User with username = [neo] already exists."
      }
    ]
  }
}
```