Sigma Code
Sigma Code is an independently maintained desktop, web, and mobile client for
coding agents. It is a downstream fork of
T3 Code with a first-party Sigma provider
connected over the open Agent Client Protocol (ACP).
Sigma Code is not affiliated with, sponsored by, or endorsed by T3 Tools, Inc.
The original T3 Code copyright and MIT license are preserved in
LICENSE; downstream and third-party attribution is documented in
NOTICE and THIRD_PARTY_NOTICES.md.
Current status
Official Windows x64 installers are published in the
Sigma Releases. Each installer
contains this desktop UI and the exact verified Sigma Runtime from the same
release, so a separate Node.js or Agent CLI installation is not required.
Release builds use that Sigma repository as their automatic-update channel.
Windows installers remain unsigned previews until a trusted signing identity is
available, so SmartScreen or Smart App Control may warn or block them. A hosted
Connect service is not configured, and cloud features stay disabled by default.
The retained upstream marketing site is reference source only and is disabled
from development, preview, build, and deployment in this downstream.
The application uses its own identities and state:
- executable:
sigma-code
- URL scheme:
sigmacode
- application ID:
io.github.hututuqqq.sigmacode
- state directory:
~/.sigma/code
It never migrates, reads, or writes ~/.t3 or the official T3 Code application
data.
The default path is Sigma Runtime + ChatGPT subscription (experimental).
In the Windows desktop app, choose a Sigma subscription model and click
Login with ChatGPT once. Sigma keeps running the task, tools, recovery,
reviewer, strategist, and persistence; model requests use the ChatGPT/Codex
subscription allowance and do not require OPENAI_API_KEY. Authentication,
allowance, and network failures are shown directly and never trigger a silent
fallback to another paid provider.
Sigma Runtime's model layer is backed by the pinned Pi directory. Settings
shows one searchable model connection per underlying provider, with API-key
and OAuth methods supplied by the trusted Runtime. The full 1,100+ model
catalog remains searchable without rendering every model in the default
picker. Models with unverified pricing require explicit confirmation for the
current task and are shown as “Price unknown”, never as $0.
Sigma Code also retains the upstream providers. Install and authenticate any
separate provider you intend to use:
- Sigma Runtime + Pi model connections: desktop artifacts include a verified
Sigma Runtime; ChatGPT, API-key, and supported OAuth logins are managed from
Sigma Code
- Codex CLI（独立 Agent）: install Codex CLI and run
codex login
- Claude: install Claude Code and run
claude auth login
- Cursor: install Cursor CLI and run
cursor-agent login
- Grok Build: install Grok Build CLI and run
grok login
- OpenCode: install OpenCode and run
opencode auth login
Development
Install the repository toolchain and dependencies:
curl -fsSL https://vite.plus | bash
vp install
On Windows:
irm https://vite.plus/ps1 | iex
vp install
Start the web and server development stack:
vp run dev
Start the desktop development build:
vp run dev:desktop
The Sigma provider automatically starts the long-lived local ACP server with
sigma acp.
Desktop artifacts must be built with a verified portable Runtime produced by
the Sigma repository:
$env:SIGMACODE_DESKTOP_SIGMA_RUNTIME = "C:\path\to\sigma\.artifacts\agent-cli-win32-x64"
vp run dist:desktop:win:x64
The build rejects missing or incomplete Runtime bundles so a distributable
installer cannot silently ship without the Sigma provider.
Documentation
See CONTRIBUTING.md before submitting downstream changes.
