Echoes the provided message back to the caller.
| name | type | description | default | 
|---|---|---|---|
| message | query | The message to echo back | Hello, World! | 
| media type | data type | description | 
|---|---|---|
| application/json | ApiEcho (JSON) | The original message | 
Throws an error containing the given input message. This is what an error response looks like.
   {
     "message": "An error message",
     "causes": [ "A list of causes", "Potentially null" ]
   }
 
The message field contains a description of the error. The causes field, if not null, contains a list of causes for the error.
Note that this never returns an echoMessage. Instead, the result (and all error results) has the above structure.
| name | type | description | default | 
|---|---|---|---|
| message | query | The error message to echo | Default error message | 
| media type | data type | description | 
|---|---|---|
| application/json | ApiEcho (JSON) | Will always be an exception |