Refact – Open-Source AI Agent, Code Generator & Chat for JavaScript, Python, TypeScript, Java, PHP, Go, and more.Extension40/100 via “custom system prompt configuration for personalized ai behavior”
Refact.ai is the #1 free open-source AI Agent on the SWE-bench verified leaderboard. It autonomously handles software engineering tasks end to end. It understands large and complex codebases, adapts to your workflow, and connects with the tools developers actually use (including MCP). It tracks your
Unique: Enables custom system prompt configuration to enforce organizational standards and coding philosophies at the AI level, allowing teams to embed best practices without code-level enforcement. This differs from tools without customization, which apply generic code generation rules.
vs others: More customizable than fixed-behavior tools because it allows teams to define AI behavior through prompts, enabling enforcement of organizational standards and domain-specific conventions without tool modifications.