What are the OAuth scopes needed to access the Zoho MCP server?

What are the OAuth scopes needed to access the Zoho MCP server?

I think I'm authenticating with the MCP server endpoint successfully using a bearer token but I can't successfully initialize an MCP session.  I'm using the official MCP Python sdk (https://github.com/modelcontextprotocol/python-sdk).

I get as far as here but I don't get much more than the callstack from the raised exception:
https://github.com/modelcontextprotocol/python-sdk/blob/9c8f763aa8ee440ff2edb034cd98ced565707b74/src/mcp/shared/session.py#L288

Maybe this is a scopes issue?

What scopes should I use during the Zoho OAuth process to access the Zoho MCP server?