oh-my-posh/docs/docs/segment-shell.md

id	title	sidebar_label
shell	Shell	Shell

What

Show the current shell name (zsh, powershell, bash, ...).

Sample Configuration

{
  "type": "shell",
  "style": "powerline",
  "powerline_symbol": "",
  "foreground": "#ffffff",
  "background": "#0077c2",
  "properties": {
    "prefix": "  "
  }
}