I got tired of debugging my AI tooling by reading HTTP traces instead of writing code. Claude Code wanted Anthropic Messages. Codex CLI wanted OpenAI Responses, and sometimes its own internal /backend-api/codex/responses path. Gemini CLI wanted Google's v1beta/models/* endpoints. Every tool acted like its protocol was the normal one. The annoying part was not auth. It was compatibility. If I wanted one local gateway for all three tools, I needed to solve three problems at once: different request schemas different streaming formats different assumptions about images, tools, and model names The Before State Before this project, "use one local proxy for all my AI coding tools" sounded simpler than it was. Claude Code expects POST /v1/messages .…