How to update Description of custom object through API

Question

I want to update Description field which appears under Custom Object Definition of a custom object via REST call. I referred Tooling and Metadata API documentation, but could not figure out a way do it. An example using curl will be helpful.

Answer 1

One option is to use the CustomObject.Description field.

Description
The object’s description. This can be useful to describe the reason for creating the object or its intended use.

If you know the Id of the custom object, then you can update the record using a PATCH call.

patchcustomobject.json

{
    "Description" : "Updated via the REST API using curl"
}

curl command

curl https://na5.salesforce.com/services/data/v35.0/tooling/sobjects/CustomObject/01I70000000IDawEAG  
  -H "Authorization: Bearer token" 
  -H "Content-Type: application/json" 
  -d @patchcustomobject.json -X PATCH

Replace the token with a valid session id (a.k.a. access token).

If you can't make a PATCH call you can do a POST instead by adding the following to the URL:

?_HttpMethod=PATCH

UPDATE

As noted by SSK in the comments, this produces the following error:

[
    {
        "message": "sObject type 'CustomEntityDefinition' is not supported. If you are attempting to use a custom object, be sure to append the '__c' after the entity name. Please reference your WSDL or the describe call for the appropriate names.",
        "errorCode": "INVALID_TYPE",
        "fields": []
    }
]

The same error occurs with the equivalent call against the SOAP version of the Tooling API.

Looking at the documentation again, I note that the Description field doesn't have "Update" under the listed Properties. It would appear that the tooling API doesn't support changing this field. You may need to resort to the Metadata API.