The bare import mcp; must expose a curated, stable surface: protocol
types, McpServer / McpClient, the UDA / reflection API, and the error
builders. Transport wiring (mcp.transport) and auth plumbing
(mcp.auth) must require an explicit opt-in submodule import and must NOT
be dumped at the top level.
Tests that the public API is tiered.
The bare import mcp; must expose a curated, stable surface: protocol types, McpServer / McpClient, the UDA / reflection API, and the error builders. Transport wiring (mcp.transport) and auth plumbing (mcp.auth) must require an explicit opt-in submodule import and must NOT be dumped at the top level.