While hyperglass does come with several built-in commands or [directives](/configuration/directives-file-reference), you can also add your own. For example, say you want to add a command that shows the BGP summary from a device:

## 1. Create the Directive

```yaml filename="directives.yaml"
show-bgp-summary:
  name: BGP Summary
  rules:
    - condition: null
      command: show bgp all summary
  field: null
```

## 2. Associate the Directive with the Device

```yaml filename="devices.yaml"
devices:
  - name: Your Router
    address: 192.0.2.1
    platform: cisco_ios
    directives:
      - show-bgp-summary
```

By default, all built-in directives are _also_ enabled. If you wish to _only_ enable directives you specify, you can use `builtins: false` as a directive:

```yaml filename="devices.yaml"
devices:
  - name: Your Router
    address: 192.0.2.1
    platform: cisco_ios
    directives:
      - builtins: false
      - show-bgp-summary
```

When this is specified, _only_ the `show-bgp-summary` directive will be enabled.