Codebuff is a CLI coding agent installed with a single npm command that edits your codebase from natural-language instructions. Instead of one monolithic model loop, it runs a multi-agent architecture — a File Picker that finds relevant context, a Planner, an Editor and a Reviewer — which the team credits for beating single-agent tools on its 175-task real-world benchmark, where it scored 61% versus Claude Code's 53%.
Open source and extensible
The full agent is open source on GitHub, and a TypeScript SDK lets developers embed Codebuff's agents in their own tools and workflows or define custom agent pipelines. Codebuff works with any tech stack, indexes the repository for deep codebase context, and emphasizes zero configuration: no IDE switch, no API key juggling for casual use.
Company background
Codebuff was founded by James Grugett, previously a co-founder of prediction-market platform Manifold, and went through Y Combinator's Fall 2024 batch. In 2026 the team launched Freebuff, a free ad-supported tier of the coding agent, alongside its credit-based paid plans — an unusual monetization experiment in the CLI agent market dominated by Claude Code, Aider and OpenAI's Codex CLI.