Test an n8n webhook from the command line with curl
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Practice safely first: node practice-receiver.js, then in another terminal:
curl -X POST http://localhost:3999/webhook-test -H "Content-Type: application/json" -d '{"hello":"world"}'

Once you're comfortable with the command shape, swap localhost:3999/webhook-test for your real
n8n webhook's Test URL (shown in the Webhook node when you click "Listen for Test Event").
