Zero

Zero is a terminal coding agent built for developers who want full control over their AI tooling. It reads your repo, edits files, runs commands, and stores every session locally on your disk. No cloud sync, no telemetry, no vendor lock-in on the model side.

The model choice is genuinely open. Zero connects to 25+ providers including OpenAI, Anthropic, Gemini, Mistral, Groq, DeepSeek, Bedrock, Vertex AI, and local options like Ollama and LM Studio. You can switch providers mid-session with /model, or point it at any OpenAI- or Anthropic-compatible endpoint.

Permissions are explicit and visible. Every side effect (file writes, shell commands, network access) is gated, with OS-level sandboxing. Autonomy is an opt-in, not the default. That makes it practical to run in CI as well as interactively.

Key capabilities:

• Headless mode for one-shot or scripted runs with JSON and stream-JSON output, plus reliable exit codes for pipelines
• MCP support in both directions: consume MCP servers over stdio, HTTP, or SSE, or expose Zero itself as an MCP server
• Spec-first runs to draft and review a plan before any file changes
• Specialist subagents to fan work out to focused sub-sessions you can inspect live
• Isolated git worktrees for risky changes you can discard if they don't pan out
• Session history that's searchable, resumable, and forkable from the command line
• Skills and plugins for encoding team conventions in markdown and extending behavior with hooks
• Scheduled agents for recurring jobs like nightly triage or dependency sweeps
• GitHub Action for PR review and CI jobs using the same agent

Sessions live in ~/.config/zero/ and API keys are stored in an encrypted local store. Unlike some other terminal agents, Zero ships as a single Go binary that runs on macOS, Linux, and Windows (x64 and arm64). Twelve contrast-audited themes are included.

It's MIT licensed. You pay your model provider, or nothing at all with a local model.