I talk to Claude a lot. It's part of my daily engineering workflow. It helps me think through projects, draft writing, and explore ideas. At some point I started wondering what it would look like to build my own interface to the API—something lean, opinionated, and designed around how I actually work rather than how someone else's TUI assumes I do.
Index is the result. It's a lightweight agent orchestration runtime written in C++. No frameworks, no HTTP libraries, no dependency manager. It talks to the Claude API over raw TLS sockets, manages multiple agents with distinct personalities and goals, and runs as an interactive REPL, a TCP server, or a one-shot CLI. The whole thing currently sits at just over 3,000 lines of code.
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