Vellium: Open-Source Desktop App Revolutionizes Creative Writing with Visual AI Controls

Vellium: Open-Source Desktop App Revolutionizes Creative Writing with Visual AI Controls

A groundbreaking open-source desktop application named Vellium is redefining the landscape of AI-assisted creative writing by eliminating the need for complex prompt engineering. Developed by an independent software creator and recently shared on Reddit’s r/LocalLLaMA community, Vellium offers a visual, slider-based interface that allows writers to dynamically control narrative parameters such as pacing, intensity, mood, and dialogue style—without ever typing a single prompt.

According to the developer, the inspiration for Vellium came from the frustration of navigating convoluted configuration menus in existing tools like SillyTavern. "I got tired of digging through SillyTavern's config every time I wanted to change the tone of a scene," the creator wrote. The result is a streamlined, intuitive environment where writers can adjust sliders for eight core narrative dimensions—Mood, Pacing, Intensity, Dialogue Style, Initiative, Descriptiveness, Unpredictability, and Emotional Depth—while their AI model generates text in real time. Behind the scenes, Vellium automatically translates these visual inputs into optimized prompt injections, removing the technical barrier that has long hindered non-technical users from harnessing the full potential of local and cloud-based LLMs.

The application features a dual-mode interface: a conversational chat mode for character development and brainstorming, and a dedicated Writer Mode for long-form storytelling. In Writer Mode, each chapter is treated as an independent narrative unit with its own set of controls—including Point of View, Creativity, Tension, Detail, and Dialogue Share—enabling writers to fine-tune the voice and texture of each section with surgical precision. Users can generate new scenes, expand existing passages, rewrite content, or summarize sections—all while continuing to interact with the AI in real time. Background generation ensures that writing flow is never interrupted.

One of Vellium’s most innovative features is its seamless integration between chat and writing environments. Characters created during casual conversations can be instantly imported into a novel’s cast, preserving personality traits, backstory, and even visual avatars pulled from the Chub AI avatar repository. The app supports importing character cards from SillyTavern V2 and JSON formats, making migration effortless for users transitioning from other platforms.

Vellium also incorporates advanced tools for worldbuilding, including keyword-activated Lorebooks that trigger contextual information during writing, and Multi-Agent Chat with automatic turn-switching—ideal for simulating complex dialogues between multiple characters. The application supports Model Control Protocol (MCP) tool calling with per-function toggles, allowing granular control over external plugins. Additionally, users can attach files and enable vision capabilities in chat, expanding the app’s utility beyond text-based generation.

Designed for accessibility and flexibility, Vellium is compatible with a wide range of local and cloud-based AI backends, including Ollama, LM Studio, OpenAI, and OpenRouter. It supports multiple languages—English, Russian, Chinese, and Japanese—and offers both light and dark themes for extended writing sessions. Export functionality allows users to save completed works in Markdown or DOCX formats, ensuring compatibility with standard publishing tools.

Though still in early development, Vellium has already garnered significant attention from indie writers and AI enthusiasts. The open-source nature of the project, hosted on GitHub, invites community contributions and feedback, accelerating its evolution. With its elegant fusion of creative intuition and AI power, Vellium may well become the new standard for writers seeking to reclaim narrative control without sacrificing simplicity.

Source: Reddit r/LocalLLaMA, https://www.reddit.com/r/LocalLLaMA/comments/1r89a4y/vellium_opensource_desktop_app_for_creative/