splash

SplashCompareHappy

Splash and Happy, compared.

Splash and Happy are both free, open-source apps for running coding agents on your own machine. Happy Desktop drives Claude, Codex and Grok through its own agent runtime, Happy Agent, which supplies the tools, sandbox and permissions, and pairs with iOS and Android apps. Splash connects to each agent over the Agent Client Protocol.

Checked 10 October 202656 sourcesNot affiliated with Happy Engineering

Splash

Helge Sverre

A desktop app for running several coding agents at once, each session in its project folder or its own git worktree. It drives agents over the Agent Client Protocol.12

splash.computer

Happy

Happy Engineering

A macOS, Windows and Linux desktop app that drives Claude, Codex and Grok through a local agent daemon with its own sandbox and permissions, plus encrypted iOS and Android apps that control sessions.3456

happy.engineering

Side by side

SplashHappy
The basics
What it is Desktop app, plus a headless server you open in a browser17 Desktop app on a local agent daemon, Happy Agent, plus iOS, Android and web clients and a terminal UI589
Release status v0.2.1, early development110 Desktop v0.0.93 (9 October 2026) with Happy Agent v0.4.86; the original happy CLI is now in maintenance mode111213
License Open source (MIT)14 Open source (MIT) for the desktop app, Happy Agent and the original CLI; adapted Grok Build code stays Apache-2.0151617
Price Free18 Free, with no Happy plan for models; voice has a capped free tier, then an in-app subscription with no published price1920212223
Platforms macOS 14+ (Apple silicon and Intel), Windows 11 x64, Ubuntu 24.04 x6424 macOS (Apple silicon and Intel), Windows x64, Linux x64 and arm64 (AppImage); iOS 15.1+, Android and a web app112523268
Built with Rust, with a Svelte 5 frontend in a webview, built on the Elyra framework27 Electron, React and TypeScript; agents, tools and the session database live in the separate Happy Agent daemon285
Agents
Agents Ships launch commands for 20 agents, including Claude Code, Codex, Copilot, Gemini, Goose, OpenCode2930 Claude, Codex, Grok and Bedrock-hosted Claude and GPT models; the original CLI also runs Antigravity, OpenClaw and any ACP agent42031
How it runs agents Agent Client Protocol over stdio, natively or through a pinned adapter for the vendor’s CLI292 Happy Agent runs the loop and tools itself; inference goes through the Claude Agent SDK, Pi’s Codex transport and xAI’s Responses API516
Agent sign-in Who pays for the model You install and sign in to each agent’s CLI yourself; Splash runs it with that login30 Reuses the Claude Code, Codex or Grok CLI login on the machine, or Bedrock credentials; requests go straight to the provider2016
Account required Splash has no accounts; splash-server asks for a token it keeps in its data folder327 None for Desktop, which uses a signed-in provider CLI; the phone app creates an account with no email or password; teams sign in to Happy Social5252333
Model and mode pickers Yes: Model, mode and effort pickers when the agent offers them34 Yes: Model, reasoning effort and permission mode can change mid-session, across providers, from the desktop or phone; the transcript stays20335
Permission requests When an agent asks before it acts Yes: Shown in the transcript and answered with the 1–9 keys; pending ones wait in Needs attention34 Yes: Four modes; in Auto, the desktop default, a read-only agent reviews actions leaving the sandbox instead of asking you. The phone can answer requests356
MCP servers Partly: Read-only list of MCP servers from Claude Code, Codex, Pi, Pool and Glue config files3436 Yes: Stdio and Streamable HTTP servers in mcp.toml; Claude Code and Codex configs aren’t imported; each MCP tool requires Auto or Full access3735
Working in parallel
Isolation per session Yes: The project folder, or a git worktree on its own branch per session34 Yes: A git worktree on a new branch when parallel work could collide, or a folder copy without git; commands run in an OS sandbox except in Full access3835
Setup scripts and dev servers No: A worktree is a plain git checkout; Splash runs no setup scripts or dev servers3439 Yes: Setup commands such as pnpm install run in each new worktree; gitignored files like .env are copied and kept in sync3840
Terminal Yes: A terminal in the session folder34 Yes: Terminals in the desktop app, including ones an agent opens; Happy Terminal offers the same harness as a TUI5419
What needs you Yes: One queue for permission requests, connection failures and finished turns, kept across restarts3442 Partly: Agent questions show in the chat and in an experimental Inbox; a macOS Dock badge counts conversations waiting on you41543
Notifications Yes: Notifies when a background session needs permission or finishes a turn; can be turned off4445 Yes: Push alerts on the phone when an agent is waiting on you or done; a completion chime on desktop2346
Agents handing off work One agent launching or messaging another No: Each session is one agent in one folder; sessions don’t hand work to each other134 Yes: Agents launch subagents, each picking its own model and running in Auto, up to three deep and five per tree, and message other agents by ID41
Scheduled tasks Agents that start without a prompt from you No: No scheduler; an agent starts when you create, continue or prompt a session27 Yes: A main session can queue a message for itself or another agent to arrive hours or days later; waits of up to a day survive restarts41
Team collaboration No: splash-server is a personal, single-user service, not a multi-user deployment7 Yes: Invite someone into a live session; team servers are self-run, and adding teammates from the sidebar isn’t built yet33
Review and shipping
Review changes Yes: Latest response, failed tools and every changed file as a diff, with a box to send feedback34 Yes: Changed files beside the chat, diffed against the merge base with origin/main; line comments in the diff go to the agent384748
GitHub Yes: Issues, pull requests and Actions runs across repositories, through the gh CLI3449 No: No GitHub views among Desktop’s documented parts; the remote server setup can install and sign in the gh CLI550
Where it runs
Cloud execution No: Agents run as child processes on your computer, or on your own server with splash-server17 No: Not offered; agents run on your computer, your own servers or a team server you run. The Vision page sketches a core agent that would live in the cloud3503351
Remote access Yes: splash-server runs on the machine with your code; you use it in a browser over an SSH tunnel. Single user.7 Yes: The Chief of Staff installs Happy Agent on a server over SSH; Desktop reaches it through built-in Tailcat with no account or open port5052
Mobile app No: No mobile app; builds cover macOS, Windows, Ubuntu and a headless server24 Yes: Encrypted iOS and Android apps and a web client: message agents, answer requests, switch models, read files and Git changes6423268
Auto-update No: Download new versions from GitHub Releases; the app does not update itself2453 Partly: On macOS the app downloads and installs its own updates, with a Preview channel; Windows and Linux builds don’t yet. The Chief of Staff upgrades Happy Agent545552
History and search
Existing agent history Conversations started outside the app Yes: Browse, preview and import conversations agents list over ACP, including ones started outside Splash3442 No: Setup finds projects in Claude Code and Codex folders from their metadata and never imports their conversations5225
Search transcripts Yes: Search titles, folders and saved transcript text, archived sessions included34 Not documented: Not documented

Where they differ

How agents connect

Happy Desktop’s daemon, Happy Agent, runs the agent loop, tools and permissions itself; for inference it calls the Claude Agent SDK, Pi’s Codex transport and xAI’s Responses API. The original happy CLI wraps the claude and codex CLIs and can start any ACP agent. Splash speaks the Agent Client Protocol with each agent, natively or through an adapter.516931292

Sandbox and permissions

Happy runs agent commands in an OS sandbox (Seatbelt on macOS, its own supervisor on Linux), optionally inside Docker, with no network unless domains are allowlisted; Full access lifts it. In Desktop’s default Auto mode, a read-only agent reviews actions that leave the sandbox instead of asking you. Splash shows each agent’s permission requests in the transcript, answered with the 1–9 keys and queued in Needs attention.354034

Where agents run

Happy runs agents on your computer, on your own servers running Happy Agent, or on team servers you host; it offers no cloud sessions. Phones connect through an encrypted relay you can self-host. Splash runs agents on your computer, or under splash-server on a machine you reach in a browser over SSH.5033365617

Price, accounts and license

Both are free and MIT-licensed. Happy documents one paid extra: voice, which moves to an in-app subscription past a free allowance. Its desktop app needs no Happy account, the phone app creates one with no email or password, and teams sign in to Happy Social. Splash has no accounts; splash-server uses a token.19212215235331418327

Around the session

Happy’s extras sit around the agent: a built-in Chief of Staff that handles setup and Happy Agent upgrades, subagents, scheduled messages, setup commands per workspace, shared sessions and phone control. Splash centers on the conversations themselves: a Needs attention queue, transcript search, importing sessions agents started elsewhere, and a GitHub view of issues, pull requests and Actions runs.524138336344249

Which one fits

Splash may suit you if

  • You want Gemini, Copilot, Goose, OpenCode and other ACP agents in one desktop app alongside Claude Code and Codex.
  • You want to import conversations your agents started outside the app and search them with the rest.
  • You want permission requests, connection failures and finished turns gathered in one Needs attention queue.
  • You want a GitHub view of issues, pull requests and Actions runs across your repositories.

Happy may suit you if

  • You want Claude, Codex and Grok in one runtime with a shared sandbox, permission modes and subagents.
  • You want to follow and answer your agents from encrypted iOS and Android apps.
  • You want setup commands and synced .env files in each new worktree.
  • You want agents on your own servers or a self-run team server, and to invite others into a session.

Sources

Facts about Happy come from its public website, documentation and repositories as they read on 10 October 2026; we haven't confirmed each one by running Happy. Facts about Splash link to its source. Products change, so check the linked pages before deciding. Something wrong or out of date? Open an issue.

  1. 1 Splash README Splash on GitHub · github.com · checked 2026-10-09
  2. 2 Agent Client Protocol agentclientprotocol.com · agentclientprotocol.com · checked 2026-10-09
  3. 3 The Open Source Desktop App for Claude Code, Codex, and Grok Happy Engineering · happy.engineering · checked 2026-10-10
  4. 4 Welcome Happy Engineering · happy.engineering · checked 2026-10-10
  5. 5 How It Works Happy Engineering · happy.engineering · checked 2026-10-10
  6. 6 Mobile Access Happy Engineering · happy.engineering · checked 2026-10-10
  7. 7 Splash README: Run as a web app over SSH Splash on GitHub · github.com · checked 2026-10-09
  8. 8 README slopus/happy on GitHub · github.com · checked 2026-10-10
  9. 9 Using the Terminal Happy Engineering · happy.engineering · checked 2026-10-10
  10. 10 Splash releases Splash on GitHub · github.com · checked 2026-10-09
  11. 11 Happy v0.0.93 slopus/happy-desktop on GitHub · github.com · checked 2026-10-10
  12. 12 Happy Agent v0.4.86 slopus/happy-agent on GitHub · github.com · checked 2026-10-10
  13. 13 Security & Encryption (Happy Coder docs) Happy Engineering · happy.engineering · checked 2026-10-10
  14. 14 LICENSE Splash on GitHub · github.com · checked 2026-10-09
  15. 15 LICENSE slopus/happy-desktop on GitHub · github.com · checked 2026-10-10
  16. 16 README slopus/happy-agent on GitHub · github.com · checked 2026-10-10
  17. 17 packages/happy-cli/package.json slopus/happy on GitHub · github.com · checked 2026-10-10
  18. 18 Download Splash splash.computer · splash.computer · checked 2026-10-09
  19. 19 Happy — Desktop & Mobile App for Claude Code, Codex & Grok Happy Engineering · happy.engineering · checked 2026-10-10
  20. 20 Models & Subscriptions Happy Engineering · happy.engineering · checked 2026-10-10
  21. 21 General FAQ (Happy Coder docs) Happy Engineering · happy.engineering · checked 2026-10-10
  22. 22 packages/happy-app/sources/realtime/RealtimeSession.ts slopus/happy on GitHub · github.com · checked 2026-10-10
  23. 23 Happy: Codex & Claude Code App Apple App Store · apps.apple.com · checked 2026-10-10
  24. 24 Splash README: Download the app Splash on GitHub · github.com · checked 2026-10-09
  25. 25 Quick Start Happy Engineering · happy.engineering · checked 2026-10-10
  26. 26 Happy: Codex & Claude Code App Google Play · play.google.com · checked 2026-10-10
  27. 27 Splash README: How it works Splash on GitHub · github.com · checked 2026-10-09
  28. 28 packages/happy-desktop-electron/package.json slopus/happy-desktop on GitHub · github.com · checked 2026-10-10
  29. 29 src/agents/registry.rs Splash on GitHub · github.com · checked 2026-10-09
  30. 30 Splash README: Agents Splash on GitHub · github.com · checked 2026-10-09
  31. 31 packages/happy-cli/README.md slopus/happy on GitHub · github.com · checked 2026-10-10
  32. 32 Splash README: Build from source Splash on GitHub · github.com · checked 2026-10-09
  33. 33 Multiplayer & Teams Happy Engineering · happy.engineering · checked 2026-10-10
  34. 34 Splash README: Features Splash on GitHub · github.com · checked 2026-10-09
  35. 35 Permissions & Sandbox Happy Engineering · happy.engineering · checked 2026-10-10
  36. 36 src/agents/customize.rs Splash on GitHub · github.com · checked 2026-10-09
  37. 37 Skills & MCP Happy Engineering · happy.engineering · checked 2026-10-10
  38. 38 Projects & Workspaces Happy Engineering · happy.engineering · checked 2026-10-10
  39. 39 src/worktree.rs Splash on GitHub · github.com · checked 2026-10-09
  40. 40 Configuration Happy Engineering · happy.engineering · checked 2026-10-10
  41. 41 Agents That Never Die Happy Engineering · happy.engineering · checked 2026-10-10
  42. 42 Splash README: Existing sessions and review Splash on GitHub · github.com · checked 2026-10-09
  43. 43 packages/happy-desktop-electron/sources/main/dockBadge.ts slopus/happy-desktop on GitHub · github.com · checked 2026-10-10
  44. 44 app/src/components/settings/General.svelte Splash on GitHub · github.com · checked 2026-10-09
  45. 45 app/src/lib/system.ts Splash on GitHub · github.com · checked 2026-10-09
  46. 46 packages/happy-desktop-electron/sources/renderer/completionChime.ts slopus/happy-desktop on GitHub · github.com · checked 2026-10-10
  47. 47 packages/happy-desktop-ui/src/ReviewComment.tsx slopus/happy-desktop on GitHub · github.com · checked 2026-10-10
  48. 48 packages/happy-desktop-state/src/happyAgent/happyAgentComposerAttachment.ts slopus/happy-desktop on GitHub · github.com · checked 2026-10-10
  49. 49 Splash README: GitHub view Splash on GitHub · github.com · checked 2026-10-09
  50. 50 Run Claude Code and Codex on a Remote Server Happy Engineering · happy.engineering · checked 2026-10-10
  51. 51 Vision Happy Engineering · happy.engineering · checked 2026-10-10
  52. 52 Chief of Staff Happy Engineering · happy.engineering · checked 2026-10-10
  53. 53 app/src/components/settings/About.svelte Splash on GitHub · github.com · checked 2026-10-09
  54. 54 packages/happy-desktop-electron/sources/main/updater.ts slopus/happy-desktop on GitHub · github.com · checked 2026-10-10
  55. 55 packages/happy-desktop-electron/sources/main/main.ts slopus/happy-desktop on GitHub · github.com · checked 2026-10-10
  56. 56 Self-Host Your Own Happy Server (Happy Coder docs) Happy Engineering · happy.engineering · checked 2026-10-10