Payload logging is disabled by default:

MTPLX_AGENT_PROXY_LOG_ENABLED=0

When disabled, the bridge stores aggregated metrics only. Do not enable payload logging on shared or public endpoints unless you understand the privacy impact.

The bridge reads the API key from:

~/.mtplx/agent-proxy-api-key

Use HTTPS in front of the bridge when exposing it outside localhost. The included ngrok launcher does that for reserved ngrok domains.

Only expose the bridge through a tunnel or reverse proxy that you control. Rotate the local API key if it was pasted into a public location.