Occ — Development skill for Claude Code

Open C Code (OCC)

A safe, open-source coding agent — capabilities aligned with Claude Code.

[](https://www.npmjs.com/package/@cnwenf/occ) [](./LICENSE) [](https://bun.sh/) [](https://docs.anthropic.com/en/docs/claude-code)

[简体中文](./README.zh-CN.md) · **English**

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What is OCC

**Open C Code (OCC)** is an open-source coding agent. Its capabilities are aligned with [Claude Code](https://docs.anthropic.com/en/docs/claude-code) (currently tracking `2.1.223` — 2.1.218 fully aligned, 2.1.219 + 2.1.221 + 2.1.223 partial, 2.1.222 staged, per OCC-46 gap report). The code is fully open, auditable, backdoor-free, and your data stays under your control.

If you worry that a closed-source CLI might hide backdoors, or that your code and credentials are uploaded to unauditable services, OCC is for you: all source is open and unobfuscated, the build is reproducible from source, and API credentials are sent only to endpoints you configure.

Positioning

• 🔓 Open & auditable — full source, no obfuscation, line-by-line reviewable.
• 🛡️ Transparent & safe — no telemetry black boxes, no hidden reporting; behavior you can supervise.
• 🎯 Capability-aligned — REPL, tool system, permission model, MCP, sub-agents, slash commands — on par with Claude Code.
• 🔧 Data sovereignty — API Key / Bedrock / Vertex / Azure credentials stay on your machine; requests go only to endpoints you specify.
• 🧩 Hackable — trim, extend, or fork subsystems; feature flags and a workspace stub layer make the boundary between live and trimmed code explicit.

Quick install

npm i -g @cnwenf/occ   # install
occ                    # launch the interactive REPL

Re