Comment by BeefySwain

I assume because the discovery is branching. If the an agent using the CLI for for GitHub needs to make an issue, it can check the help message for the issue sub-command and go from there, doesn't need to know anything about pull requests, or pipelines, or account configuration, etc, so it doesn't query those subcommands.

Compare this to an MCP, where my understanding is that the entire API usage is injected into the context.