[BUGBASH] Learning may take more loops than necessary

### Describe the bug

Attempting to use learn to determine which command is be for your use case can help guide the agent in the right direction, but it may take more back-and-forth communication than necessary due to how `subscription` requirement is reported.

### Expected behavior

When learning, subscription should be determined to be required and passed through either `--subscription` or the environment variable.

### Actual behavior

If there isn't context about subscription or it's not set in the environment variable, the agent will attempt to call the MCP server without it as it doesn't know it's required,

I started with `List my Storage blobs with learn=true` and the agent correctly assessed that I didn't specify a Storage account to list in, so it attempted to list those first but since subscription isn't marked as required it failed.

### Reproduction Steps

Use `List my Storage blobs with learn=true` as the initial command. Iterate through until learning determines which command(s) should be used.

### Environment

_No response_