If you use the Node-RED integration for HA, there is a simple way to trigger actions with a basic HTTP GET request, without any headers, tokens or payload. I have an IP door bell that can only execute simple HTTP requests, and this works perfectly:
Use the http in
node in Node-RED to expose a new HTTP endpoint. This endpoint can be triggered by a simple HTTP GET, i.e. by calling the URL from a web browser. Don’t forget to combine the node with a http response
node to send back a success status code 200.
[{"id":"ef4e4794.3c12a8","type":"http in","z":"9d33a910.bd3758","name":"","url":"switch-light","method":"get","upload":false,"swaggerDoc":"","x":170,"y":100,"wires":[["1d707ade.fdea35","adc182c0.51cc5"]]},{"id":"1d707ade.fdea35","type":"http response","z":"9d33a910.bd3758","name":"","statusCode":"200","headers":{},"x":220,"y":140,"wires":[]},{"id":"adc182c0.51cc5","type":"api-call-service","z":"9d33a910.bd3758","name":"","server":"cb38d2a3.10198","version":1,"debugenabled":false,"service_domain":"light","service":"toggle","entityId":"light.buro","data":"","dataType":"json","mergecontext":"","output_location":"","output_location_type":"none","mustacheAltTags":false,"x":420,"y":100,"wires":[[]]},{"id":"cb38d2a3.10198","type":"server","z":"","name":"Home Assistant"}]
This new endpoint would be available under the URL:
http://homeassistant:1880/endpoint/switch-light
(Replace “homeassistant” with your domain or IP address!)
Each request would toggle the HA light entity.