1Code

1Code.dev

Open-source coding agent client. Run Claude Code, Codex, and more - locally or in the cloud.

By 21st.dev team

Highlights

• Multi-Agent Support - Claude Code and Codex in one app, switch instantly
• Visual UI - Cursor-like desktop app with diff previews and real-time tool execution
• Custom Models & Providers (BYOK) - Bring your own API keys
• Git Worktree Isolation - Each chat runs in its own isolated worktree
• Background Agents - Cloud sandboxes that run when your laptop sleeps
• Live Browser Previews - Preview dev branches in a real browser
• Kanban Board - Visualize agent sessions
• Built-in Git Client - Visual staging, diffs, PR creation, push to GitHub
• File Viewer - File preview with Cmd+P search and image viewer
• Integrated Terminal - Sidebar or bottom panel with Cmd+J toggle
• Model Selector - Switch between models and providers
• MCP & Plugins - Server management, plugin marketplace, rich tool display
• Automations - Trigger agents from GitHub, Linear, Slack, or manually from git events
• Chat Forking - Fork a sub-chat from any assistant message
• Message Queue - Queue prompts while an agent is working
• API - Run agents programmatically with a single API call
• Voice Input - Hold-to-talk dictation
• Plan Mode - Structured plans with markdown preview
• Extended Thinking - Enabled by default with visual UX
• Skills & Slash Commands - Custom skills and slash commands
• Custom Sub-agents - Visual task display in sidebar
• Memory - CLAUDE.md and AGENTS.md support
• PWA - Start and monitor background agents from your phone
• Cross Platform - macOS desktop, web app, Windows and Linux

Features

Run coding agents the right way

Run agents locally, in worktrees, in background - without touching main branch.

• Git Worktree Isolation - Each chat session runs in its own isolated worktree
• Background Execution - Run agents in background while you continue working
• Local-first - All code stays on your machine, no cloud sync required
• Branch Safety - Never accidentally commit to main branch
• Shared Terminals - Share terminal sessions across local-mode workspaces

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UI that finally respects your code

Cursor-like UI with diff previews, built-in git client, and the ability to see changes before they land.

• Diff Previews - See exactly what changes the agent is making in real-time
• Built-in Git Client - Stage, commit, push to GitHub, and manage branches without leaving the app
• Git Activity Badges - See git operations directly on agent messages
• Rollback - Roll back changes from any user message bubble
• Real-time Tool Execution - See bash commands, file edits, and web searches as they happen
• File Viewer - File preview with Cmd+P search, syntax highlighting, and image viewer
• Chat Forking - Fork a sub-chat from any assistant message to explore alternatives
• Chat Export - Export conversations for sharing or archival
• File Mentions - Reference files directly in chat with @ mentions
• Message Queue - Queue up prompts while an agent is working

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Plan mode that actually helps you think

The agent asks clarifying questions, builds structured plans, and shows clean markdown preview - all before execution.

• Clarifying Questions - The agent asks what it needs to know before starting
• Structured Plans - See step-by-step breakdown of what will happen
• Clean Markdown Preview - Review plans in readable format
• Review Before Execution - Approve or modify the plan before the agent acts
• Extended Thinking - Enabled by default with visual thinking gradient
• Sub-agents - Visual task list for sub-agents in the details sidebar

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Background agents that never sleep

Close your laptop. Your agents keep running in isolated cloud sandboxes with live browser previews.

• Runs When You Sleep - Background agents continue working even when your laptop is closed
• Cloud Sandboxes - Every background session runs in an isolated cloud environment
• Live Browser Previews - See your dev branch running in a real browser

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Connect anything with MCP

Full MCP server lifecycle management with a built-in plugin marketplace. No config files needed.

• MCP Server Management - Toggle, configure, and delete MCP servers from the UI
• Plugin Marketplace - Browse and install plugins with one click
• Rich Tool Display - See MCP tool calls with formatted inputs and outputs
• @ Mentions - Reference MCP servers directly in chat input

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Automations that work while you sleep

Trigger agents from GitHub, Linear, Slack, or manually from git events. Auto-review PRs, fix CI failures, and complete tasks - all configurable.

• @1code Triggers - Tag @1code in GitHub, Linear, or Slack to start agents
• Git Event Triggers - Run automations on push, PR, or any git event
• Conditions & Filters - Control when automations fire
• Execution Timeline - Visual history of past runs
• Silent Mode - Toggle respond-to-trigger for background automations

Automations require a Pro or Max subscription. Learn more at 1code.dev/agents/async.

API

Run coding agents programmatically. Point at a repo, give it a task - the agent runs in a sandbox and delivers a PR.

curl -X POST https://1code.dev/api/v1/tasks \
  -H "Authorization: Bearer YOUR_API_KEY" \
  -d '{
    "repository": "https://github.com/your-org/your-repo",
    "prompt": "Fix the failing CI tests"
  }'

• Remote Sandboxes - Isolated cloud environment, repo cloned, dependencies installed
• Git & PR Integration - Agent commits, pushes branches, opens PRs automatically
• Async Execution - Fire and forget, poll for status or get notified
• Follow-up Messages - Send additional instructions to a running task

Learn more at 1code.dev/agents/api

Installation

Option 1: Build from source (free)

# Prerequisites: Bun, Python 3.11, setuptools, Xcode Command Line Tools (macOS)
bun install
bun run claude:download  # Download Claude binary (required!)
bun run codex:download   # Download Codex binary (required!)
bun run build
bun run package:mac  # or package:win, package:linux

Important: The claude:download and codex:download steps download required agent binaries. If you skip them, the app may build but agent functionality will not work correctly.

Python note: Python 3.11 is recommended for native module rebuilds. On Python 3.12+, make sure setuptools is installed (pip install setuptools).

Option 2: Subscribe to 1code.dev (recommended)

Get pre-built releases + background agents support by subscribing at 1code.dev.

Your subscription helps us maintain and improve 1Code.

Development

bun install
bun run claude:download  # First time only
bun run codex:download   # First time only
bun run dev

Feedback & Community

Join our Discord for support and discussions.

License

Apache License 2.0 - see LICENSE for details.