Claude Code plugin credentials: what the new keychain storage does and doesn't do

Claude Code 2.1.83 shipped plugin credential management. It's worth understanding exactly what it does before you build on top of it, because the security story is better than most people expect in some ways and the design pattern around it matters more than the feature itself. What shipped When a user installs a plugin, Claude Code now prompts for any configuration it needs upfront — API keys, tokens, whatever the plugin declares. Those values go into the OS keychain. macOS Keychain on Mac, Windows Credential Manager on Windows. Not a config file. Not ~/.claude/settings.json . Not a .env sitting in your project directory. The immediate practical win: credentials don't end up in plaintext somewhere that gets accidentally committed to git, scraped by a background process, or left on a shared machine. There's a companion feature in the same release: CLAUDE_CODE_SUBPROCESS_ENV_SCRUB=1 . This strips credentials from subprocess environments — the bash tool, hooks, and MCP stdio servers. Mor