Minimal mode: skip hooks, LSP, plugin sync, attribution, auto-memory, background prefetches, keychain reads, and CLAUDE.md auto-discovery. Sets CLAUDE_CODE_SIMPLE=1. Anthropic auth is strictly ANTHROPIC_API_KEY or apiKeyHelper via --settings (OAuth and keychain are never read). 3P providers (Bedrock/Vertex/Foundry) use their own credentials. Skills still resolve via /skill-name. Explicitly provide context via: --system-prompt[-file], --append-system-prompt[-file], --add-dir (CLAUDE.md dirs), --mcp-config, --settings, --agents, --plugin-dir.