Show HN: 1667, a terminal UI for writing fiction with language models

1667 is a terminal-based writing tool that uses language models to help authors generate fiction, displaying multiple AI-generated paragraphs side-by-side in a browsable tree so writers can explore different narrative directions. The tool prioritizes user privacy by running locally with user-provided API keys, storing files on disk, and including no analytics, telemetry, or account requirements. It's available for macOS, Linux, and Windows through multiple installation methods.