Best Open Source Alternatives to OpenAI Codex CLI

Self-improving AI agent with built-in learning loop, multi-platform chat, and serverless deployment.

Open-source AI agent bringing Gemini's power to your terminal with MCP support.

Open-source terminal coding agent in Rust with MCP support, model flexibility, and community-driven development.

DeepSeek-native AI coding agent for terminal with cache-stable context, plugins, and multi-model support.

Open-source AI coding agent for the terminal with MCP, subagents, and multi-provider support.

Use ChatGPT Web models, including Pro, natively inside Codex with tools, streaming, and images without spending Codex qu

Fast-agent is a flexible CLI-first framework for coding, building, and evaluating AI agents with MCP, ACP, and A2A suppo