将JSON响应解组为Go中的两种结构类型之一

I am working with a 3rd party API endpoint that can return one of two top-level JSON objects for the same HTTP status code. I have not been happy with the solutions I have found so far so I came up with the following solution using embedded types:

type TokenError struct {
    Error            string `json:"error"`
    ErrorDescription string `json:"error_description"`
}

type Token struct {
    AccessToken string `json:"access_token"`
    ExpiresIn   int    `json:"expires_in"`
    TokenType   string `json:"token_type"`
}

type TokenResponse struct {
    *TokenError
    *Token
}

With the above types, I can do a single unmarshal and some simple checks:

var tokenResponse TokenResponse
err = json.Unmarshal(body, &tokenResponse)
if err != nil {
    fmt.Printf("Error parsing response %+v
", err)
}

if tokenResponse.TokenError != nil {
    fmt.Printf("Error fetching token: %+v
", tokenResponse.TokenError)
    return
}

if tokenResponse.Token != nil {
    fmt.Printf("Successfully got token: %+v
", tokenResponse.Token)
    return
}

I am wondering the following:

• Is this an anti-pattern or bad design for some reason? (Assuming I don't expose that TokenResponse type outside of the package...)
• Is there some easier solution to this problem that I have overlooked?