A Go gateway that makes OpenCode Zen speak fluent OpenAI and Anthropic

What it does It’s a single Go binary that sits between your OpenAI- or Anthropic-shaped clients and OpenCode Zen / Zen Go upstreams. It translates between three protocols — Chat Completions, Responses, and Anthropic Messages — handling text, images, reasoning, and tool calls in both JSON and SSE. It also manages upstream keys and proxies, with separate pools for Zen and Go tiers, retries, and session affinity. The WebUI ships inside the executable; no Node.js or database needed.

The interesting bit Cross-protocol translation goes through a common representation, and the README is refreshingly honest about what that costs: Chat JSON output constraints and seed don’t survive the trip to Anthropic Messages. Meanwhile, requests already in the upstream’s native protocol are relayed verbatim rather than mangled through translation — a sensible split. There’s also a System One endpoint for structured state-plus-questions payloads, relayed as-is.

Key highlights

• Anonymous Zen access via the OpenCode public credential, with automatic fallback to authenticated tiers when it fails
• Direct, HTTP, HTTPS, SOCKS5, and SOCKS5H proxy support, including a proxy file for rotation
• Sticky sota / sweet model groups with ordering, failure fallback, and streaming protection
• Hot config reload with validation before a replacement gateway takes over
• Management port with a Playground, quota dashboard, token stats, and live logs

Caveats

• No embeddings, file uploads, image generation, or Responses retrieval/cancellation; no conversation history storage — clients supply their own context
• Cross-protocol requests lose some provider-specific options; unsupported content or tool types may be rejected
• The management console guide is Chinese-only, matching the project’s documentation lean

Verdict If you have OpenCode Zen or Go credentials and want to point standard OpenAI/Anthropic tooling at them — with pooling and failover for free — this is a well-engineered shim. If you need embeddings or history management, look elsewhere.