Codebuff launched in late 2024 as a Y Combinator-backed multi-agent CLI coding tool. Where most coding agents used a single model for all tasks, Codebuff separated concerns into specialised sub-agents: a context picker agent chose which files were relevant, a planner agent mapped the implementation approach, an editor agent wrote the code, and a reviewer agent checked the output.
Notably, Codebuff offered a fully free tier called “Freebuff” with no subscription required and no credit limits, making it one of the few capable coding agents with zero barrier to entry. The Apache 2.0 licence allowed unrestricted commercial use.
Codebuff represented a broader trend toward specialised agent architectures — the recognition that a single LLM instance handling context selection, planning, implementation, and review simultaneously created bottlenecks and quality issues that dedicated sub-agents could avoid.