Credits

Kindred Spirit stands on the work of many others. This is a summary; every library, model, dataset, service and source, with its licence, is in THIRD_PARTY_NOTICES.md. If something is missing or wrong, please open an issue.

Made with AI, openly

Kindred Spirit is written with Claude Code, Anthropic's agentic coding tool. Its author directs the work: the ideas and design decisions, the playtests, the feedback, and the approval of every change. Claude does most of the writing.

• What Claude wrote: most of the code (the mod, her brain, the local services, the dashboard), the tests, the documentation, research summaries, the scripts that draw her skins and make the demo video and its music, and this website.
• Which model: Claude Opus 5.5, for the whole project so far.
• Pip herself uses AI while you play: her conversation is generated live by the AI the player chooses (Google's Gemini by default), her deeper thinking can run on Anthropic's Claude, and her voice comes from a speech model on the player's computer. What she says is AI-generated and can be wrong.
• Research summaries are AI-written from the cited papers and pages; check the sources for anything that matters.

The mod

Fabric Loader, Fabric API and Loom (Apache-2.0, MIT), Gradle, JUnit 5 and Gson, built with OpenJDK. It runs in Minecraft Java Edition by Mojang Studios, which isn't distributed with it. Pip's skins, textures and icon are original art made for this project.

Her brain and voice

• whisper.cpp and OpenAI's Whisper (MIT) to hear you, with Silero VAD (MIT).
• Kokoro-82M by hexgrad (Apache-2.0) for her voice, through kokoro-onnx and ONNX Runtime (MIT), with phonemizer and eSpeak NG (GPL-3.0, installed on your computer, not distributed).
• BAAI's bge-small (MIT) through fastembed (Apache-2.0) for understanding and memory search.
• websockets, NumPy, soundfile, Pillow and pytest, and Python itself.

Knowledge and game data

• The Minecraft Wiki contributors, under CC BY-NC-SA 3.0: the knowledge base each player builds on their own computer (not distributed by this project).
• minecraft-data by PrismarineJS (MIT) for recipes, foods and mining data.
• minecraft-circles-schematics by Greaby (CC0-1.0) for the circle blueprints.

Research and inspiration

Studied, with no code copied: research on language agents and memory (CoALA, Talker-Reasoner, SwiftSage, Generative Agents, MemGPT, Mem0, Zep, ReAct), Minecraft agents (Voyager, JARVIS-1, MineCollab and Mindcraft, Mineflayer, Baritone, Carpet, Automatone), the OCC model of emotions behind her heart, design notes from MCPFabric, and the idea of a companion who is always there from Verity JE. Kindred Spirit isn't a fork of it: none of its code or assets are used.

The demo video

Filmed by the game itself from a script, in a test world. The music is generated from scratch by a script in the repository (no samples); the player's voice is synthesized with Kokoro.

This website

Plain HTML and CSS with system fonts, built by a small script with no dependencies, hosted on Firebase Hosting. The pictures are stills from the demo video and the project's own art.