Automation with curl (Home Assistant)

Would this be the correct curl command to send an open command?
$curl -X POST -Hcontent-type:application/x-www-form-urlencoded -d access_token=YYYYYYYY&arg=open

where XXXXXXX is deviceid and YYYYYYYY is the token.

Yes, but it also works without content-type header:

curl -d arg="open" -d access_token=YYY-ACCESS-TOKEN-YYY

Please find more details and examples in Particle Cloud API. The list of supported functions, variables and events can be found in Garadget’s Firmware at GitHub.

I look forward to seeing more info about your project when finished.

For those who’s still finding this older post: here’s now a native Garadget support in Home Assistant.