Install globally — one command, no config required to start.
Runs on port 4100 by default. Proxies to Anthropic transparently.
Set ANTHROPIC_BASE_URL in your shell or in Claude Code settings. Your existing ANTHROPIC_API_KEY stays the same — RelayPlane forwards it to Anthropic.
Or add it to your ~/.zshrc / ~/.bashrc to persist across sessions.
That's it. Claude Code now routes through RelayPlane. Run relayplane stats to see your savings.
RelayPlane classifies each request before it hits Anthropic. Simple tasks go to Sonnet. Complex work stays on Opus. No config needed.
Max plans have two separate rate limit pools: one for all models, one for Sonnet specifically. When RelayPlane routes a simple task to Sonnet, it draws from the Sonnet pool — leaving your Opus quota untouched for the complex work that actually needs it. The result: your plan goes further. You hit the wall less often.
API key users: routing to Sonnet directly reduces cost per request (~5x cheaper than Opus for simple tasks).
Circuit breaker included. If RelayPlane goes down, Claude Code talks directly to Anthropic. No downtime, no disruption. Your ANTHROPIC_API_KEY is forwarded directly — RelayPlane never stores it.
$5,459 saved on $499 spent = 91.6% reduction. This is from a single account running Claude Code for agentic coding across a production codebase for 90 days.