What it does Claude Relay Service is a Node.js/Redis proxy you run yourself. You OAuth-link multiple Claude accounts, issue per-user API keys, and route traffic through your own box so a small group can share a Max subscription without feeding prompts to a random mirror site. It also supports Codex CLI, Gemini-CLI, and Droid clients.

The interesting bit The “carpool” angle is the real pitch: the README openly frames this as a way to split a $200 Claude Code Max plan among friends, with per-key rate limits and usage stats so everyone pays their share. That honesty is refreshing, even if the legal footing is shaky.

Key highlights

• Multi-account rotation with automatic failover when an account hits 503/5xx errors
• Per-key controls: rate limits, concurrency caps, model allowlists, and client restrictions
• Web dashboard for usage stats and cost tracking
• Docker Compose setup with one-liner install script (curl | bash via pincc.ai)
• Supports HTTP/SOCKS5 proxies if you want each Claude account on a different IP

Caveats

• The README itself warns this likely violates Anthropic’s Terms of Service; author disclaims all liability
• v1.1.248 and below had a critical auth-bypass vulnerability; upgrade to v1.1.249+ or migrate to the author’s newer CRS 2.0 project
• Chinese cloud hosts (Aliyun, Tencent Cloud) are reportedly blocked by Cloudflare when hitting Anthropic’s API

Verdict Worth a look if you’re technically self-sufficient, privacy-paranoid, and comfortable with the TOS gamble. If you just want cheap API access, the commercial mirrors mentioned in the README are probably less headache.