OptionallogoutWhether the agent supports the logout method.
Optional. Omitted or null both mean the agent does not advertise support.
Supplying {} means the agent supports the logout method.
Optional_The _meta property is reserved by ACP to allow clients and agents to attach additional metadata to their interactions. Implementations MUST NOT make assumptions about values at these keys.
See protocol docs: Extensibility
Authentication-related capabilities supported by the agent.