The Databricks MCP integration was dropping connections because the OAuth token response was missing fields that Unity Catalog requires to store credentials per user. The token response now includes the fields Unity Catalog expects, the authorization server metadata is complete, and the authorize redirect follows RFC 9207. Credentials persist across sessions instead of forcing re-authentication.
Malformed requests to the token endpoint now return a proper 400 instead of a 500, so connection errors surface with a status code that actually reflects what went wrong.