Antigravity CLIvsClaude Code

The headless terminal-first autonomous coding agent and interactive TUI for fast keyboard-driven engineering and subagent orchestration.

Antigravity CLI (agy) is Google's terminal-native autonomous coding agent built for developers who thrive in keyboard-driven, shell-centric workflows. Designed to run seamlessly in local terminals, tmux sessions, and remote SSH environments, the CLI strips away graphical overhead to deliver lightning-fast agent interaction and deep Unix pipeline integration.

Anthropic's terminal-native autonomous software engineering agent that pairs Claude 3.5 & 3.7 Sonnet with full shell agency.

Claude Code is Anthropic's revolutionary terminal-native autonomous software engineering agent, embedding the industry-leading reasoning capabilities of Claude 3.5 and 3.7 Sonnet directly into the developer's shell.

• Concurrent Subagent Delegation: Spawns specialized background agents to tackle complex programming tasks in parallel. Subagents operate in isolated branched workspaces to run unit tests, audit code security, or perform deep documentation lookups. The primary agent receives structured updates reactively without locking the terminal session.
• Terminal Sandboxing & Granular Permissions: Delivers fine-grained execution policies ranging from strict user review to autonomous sandbox execution. Developers can configure precise command allowlists, file access boundaries, and network permissions. The safety boundary prevents accidental regressions or destructive shell commands during automated cycles.
• First-Class AGY Customization Ecosystem: Loads custom skills, operational rules, lifecycle hooks, and sidecar processes directly from the user or project directory. It natively speaks the Model Context Protocol (MCP) to interface with external developer tools and APIs. Workflows can be automated using declarative slash commands like /plan, /goal, and /schedule.
• Reactive Messaging & Task Scheduling: Built on an asynchronous event architecture that eliminates CPU-wasting polling loops. The CLI includes a native cron scheduler and one-shot timers to execute recurring background tasks and alerts. It functions both as an interactive pair programmer and a 24/7 background development daemon.

• Autonomous Full-Shell Agency: Executes terminal commands, manages git branches, runs linters, and executes complex test suites without human hand-holding. The agent autonomously diagnoses test failures, modifies source files, and re-runs assertions until green.
• Surgical Search-and-Replace File Modification: Applies edits with pinpoint accuracy using semantic search-and-replace patterns rather than whole-file overwrites. This eliminates syntax regressions, preserves formatting conventions, and speeds up multi-file refactors.
• Prompt Caching Economic Advantage: Natively leverages Anthropic's prompt caching architecture to retain large repository indexes and conversational history at a 90% discount. Developers can run deep, multi-turn pair programming sessions with negligible token expenditure.
• Deep Semantic Codebase Indexing: Combines ripgrep and tree-sitter AST parsing to map project architectures in seconds. The agent comprehends relationships between disparate modules, enabling high-confidence cross-service refactoring across legacy and modern codebases.

• Blazing-fast terminal execution ideal for remote SSH, tmux, and Vim/Neovim power users
• Native subagent spawning with branched workspaces enables true parallel multitasking
• Comprehensive customization via AGY skills, rules, hooks, and Model Context Protocol (MCP)

• Unmatched coding reasoning and accuracy powered by Claude Sonnet models
• Surgical search-and-replace editing prevents code regressions and saves tokens
• Prompt caching slashes recurring API expenses by up to 90%

• Requires familiarity with shell environments and command-line workflows

• Terminal-only tool requiring familiarity with shell environments and API billing