How to set ColorLoop for bulb via yamal

[teal ledge]

Device: https://www.zigbee2mqtt.io/devices/TS0505B_1.html#tuya-ts0505b_1

I have the above light bulb (zigbee2MQTT) which also have a "colorloop" mode. It's selectable in "Expose-Functions > Effect"
I've found if I toggle the bulb off and on again, the effect is always gone (just general glowing bulb).
Even if I set the "Color power on behavior" to "previous" the effect is gone!

So, I've tried to trigger this mode by an automation, but wasn't able to do so, as I didn't found an entry to set "effects" on this device via HA Automation dialog.

Because of this, I want to understand more in detail, how to setup and use HA with yaml-files, as I assume, that it might be possible to set the right field-value pair in yaml-config (maybe like described in https://www.zigbee2mqtt.io/devices/TS0505B_1.html#effect-enum)

Can anybody give me a hint, where to start to solve this?
Thx. a lot in advanced.

[rancid knot]

Do you not see Effect in the list of options in the automation UI after you select light.turn_on the light entity in the automation UI?

in YAML it would be

- service: light.turn_on
  data:
    entity_id: light.whatever
    effect: supercooleffect

[teal ledge]

Ah, thanks a lot. I was just in the device-dialog. Now in "Light" dialog, I see this option.

But just for me to learn something. Where can I find an overview or documentation, which yaml fields a service at least can handle

BTW: Is there a way to start with a random color (or set a random-color by a click on my lightSwitch)?

[rancid knot]

the docs for the integration (in this case, the light integration)

[teal ledge]

is there some kind of helper that I could use in the bulb to generate a random-color ...e.g. for xy_color parameter?

Found something here... I'll try this: https://community.home-assistant.io/t/set-a-random-color-on-a-light/73145