DL-511

The door rejects, on every layer, MCP oauth.clientSecret, auth.clientSecret, envPolicy, headerPolicy, URL userinfo and secret-named query keys in url, auth.tokenUrl, and URL-shaped args, exaApiKey= in args, and any env or headers value that is neither a !command nor an env name; CD-3’s MUST is revised to these fields.

Status: Active (Matt, 2026-10-13)