Claude HUD

Open-source extensible AI agent by Block

Autonomous coding agent from Block (Square) that works with any LLM through MCP-first extensibility. Apache 2.0 licensed with 47K+ GitHub stars and a Linux Foundation AAIF founding project. Designed for terminal-based workflows with deep tool integration, making it a strong open-source option for developers who want agent-assisted coding without vendor lock-in.

Open-source AI agent framework with persistent memory, reusable skills, tools, and messaging gateways

Hermes Agent is an open-source AI agent framework with persistent memory, reusable skills, 40+ tools, cron jobs, and messaging gateways.

Making all software agent-native from the CLI

Universal bridge from HKUDS that makes any GUI software accessible to AI coding agents through command-line interfaces. Instead of requiring manual GUI interaction, it exposes application functionality as CLI commands agents can invoke programmatically. Addresses a core challenge in agentic development: most software targets human graphical interaction, but AI agents work best through text-based command interfaces.

xAI's terminal coding agent with parallel subagents and worktree-aware automation

Grok Build is xAI's terminal-first coding agent for planning, editing, testing, and reviewing code from a local CLI. The early beta exposes subagent controls, worktree mode, headless JSON output, best-of-N parallel attempts, sandbox profiles, and experimental memory. It fits developers comparing Claude Code, Codex, and Gemini CLI for local agentic workflows with deeper parallel execution.

Fast, native terminal emulator

GPU-accelerated terminal emulator written in Zig by Mitchell Hashimoto (HashiCorp co-founder). Native UI rendering on macOS and Linux. Supports ligatures, true color, Kitty graphics protocol, and splits/tabs. Configurable via a simple key-value file with sensible defaults. Open-source with 20K+ GitHub stars and a focus on correctness, speed, and minimal resource usage. Growing as a modern alternative to iTerm2, Alacritty, and WezTerm.

Anthropic's agentic coding CLI

Anthropic's agentic CLI coding tool that delegates complex tasks to Claude directly from the terminal. Understands entire codebases via automatic context gathering, edits multiple files, runs shell commands, and manages Git workflows autonomously. Supports CLAUDE.md for persistent project instructions, integrates with VS Code and JetBrains, and uses Claude Opus/Sonnet with extended thinking for complex architectural decisions. Built for terminal-first developers.

OpenAI coding agent for app, editor, terminal, and cloud work

Codex is OpenAI's coding agent for software development across the Codex app, editor, terminal, and cloud tasks. It helps write, review, debug, refactor, and automate code, with ChatGPT plan access for managed surfaces and API-key usage for CLI, SDK, and IDE workflows. The open-source CLI and SDK support local repository work, while cloud features add GitHub review, Slack/Linear integrations, worktrees, skills, MCP, and automations.

Open standard for portable skills across AI agents

Agent Skills is the open SKILL.md folder specification for packaging reusable instructions, scripts, references, and assets that compatible AI agents load through progressive disclosure. Originally developed by Anthropic and released as an open standard, it defines the portable format itself—not an example library, marketplace, or hosted agent product.

Continuous local code-review loops for commits produced by AI coding agents

roborev is an MIT-licensed local review system that checks every commit in the background, stores findings in a review queue, and feeds actionable issues back into AI coding sessions. Git hooks, a TUI, branch and dirty-tree analysis, Codex and Claude agent hooks, plus iterative fix/refine commands turn review into a continuous agent workflow.