ai-agent

Nucleoid

Logic Language for LLMs πŸŒ±πŸ‹ Build World Models 🌍
769 stars33 forksRustUpdated 8/22/2026100% free Β· open source
What it does

Nucleoid allows you to build and interact with world models using a logic language for large language models (LLMs), enabling more structured and coherent output.

When to use it
  • β€’You need to generate text based on specific rules or constraints.
  • β€’Your application requires a deeper understanding of the relationships between entities in a domain.
  • β€’You want to build a custom AI agent that can reason about the world in a more human-like way.
Ready-to-paste prompt
./target/release/nucleoid -i 'model.nucleoid' -q 'SELECT * FROM entities WHERE type = "person";
Heads up: Nucleoid requires Rust and the Cargo package manager to be installed on your system, so ensure you have these prerequisites before attempting to build and run Nucleoid.
Saves to your device
Use with Claude
New

Skip the builder β€” one click puts this in Claude, Cursor, Antigravity and more.

πŸ› οΈ Technical setup

Expect 20–40 minutes in a terminal β€” or let your AI agent drive it.

Try it instantly β€” no install
Claude Code
mkdir -p ~/.claude/skills/nucleoid && curl -fsSL https://workflowstacks.com/api/skills/nucleoid/claude-skill -o ~/.claude/skills/nucleoid/SKILL.md
Open in another AI app

Opens the app with this repo with the prompt ready to go β€” no copy-paste needed.

Connect the whole catalog (MCP)
claude mcp add --transport http workflowstacks https://workflowstacks.com/api/mcp

Adds a WorkflowStacks connector to Claude Code: search and load any skill here by chatting.

How Nucleoid works
Codeflow
Free to inspect

Nucleoid is a medium Rust project (~12k lines across 166 code files, plus 24 test files). Expect some technical setup β€” comfortable with a terminal, or ask a developer. Last commit a month ago, Apache-2.0 license, has a test suite.

Size
Medium codebase
~12k lines Β· 166 code files Β· ~2 h to skim
Setup
Some technical setup
Comfortable with a terminal? 20–40 min. Otherwise ask a dev.
Runs on
Rust
No API keys detected
Rust 100%
Where to start reading
  1. 1
    README.md
    Start here β€” what it does and how to install it
  2. 2
    CLAUDE.md
    The instructions the AI actually follows
  3. 3
    src/main.rs
    Where the program starts running
  4. 4
    Cargo.toml
    Dependencies and the commands it exposes
  5. 5
    ref/src/cache.js
    Inside ref/src/ β€” the main logic begins here
What's in each folder
ref/src/Core code β€” the actual logic113 files
src/Core code β€” the actual logic47 files
docs/Documentation14 files
examples/Examples you can copy3 files
ref/arc/Folder828 files
dataset/Data files23 files
synth/Folder21 files
tests/Tests β€” proof it works10 files
READMEHas testsDocumentedCI checksExamples includedApache-2.0 licenseUpdated this month
Quick Actions
Details
Creator
NucleoidAI
Language
Rust
Category
ai-agent
Published
7/11/2021

Are you the creator of this tool? Claim your listing β†’ and earn 85% of every sale.