Self-signed Portainer instances (e.g. internal LAN at 10.1.1.43:9443) caused all wrapper calls to fail silently with HTTP 000. Setting PORTAINER_INSECURE=1 passes -k to curl, bypassing certificate verification and unblocking API calls to such instances. Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>