fractal

Fractal is an open-source framework for building hierarchical AI coding agents. It enables a top-level agent to decompose a complex task into smaller subtasks and delegate each to a child agent running in an isolated git worktree. This isolation ensures that code changes for each subtask are contained in separate branches, facilitating parallel development and conflict-free merging. The system provides configurable constraints to control resource usage: depth limits restrict how many levels of delegation are allowed, cost limits cap the monetary expenses (such as API calls to LLMs), and time limits bound the total execution duration. These safeguards prevent runaway agent processes and allow safe integration into continuous development workflows. Fractal is designed for software engineering tasks, such as implementing features across multiple files, refactoring large codebases, or fixing bugs that span several modules. By distributing subtasks to specialized child agents, each focused on a delimited scope, the overall solution can be built more efficiently and with better local coherence. The git worktree mechanism naturally aligns with version control best practices, enabling easy review of each agent’s contribution.

Category

AI Agents

Pricing

Open Source

Official website: https://github.com/plasma-ai/fractal

Canonical LambdaBase page: https://www.lambdabase.com/tools/fractal