claude-code-router Anthropic-to-OpenAI translation over a local gateway

Facts

• CCR listens on one local endpoint (default http://127.0.0.1:3456); agents point at it, and CCR selects provider, model and account per request from profiles, conditions and rewrites. [source]
• A provider entry carries a protocol choice (OpenAI Chat, OpenAI Responses, Anthropic Messages, Gemini); the README advertises "protocol probing" and "connectivity checks" when a custom endpoint is added. [source]
• Routing supports conditions on headers and bodies, prefixes, rewrites, retries and ordered fallback models. [source]
• The project is no longer only a Claude Code shim: version 3.1.1 (2026-09-16) presents a desktop app plus npm CLI plus Docker image, and lists ten agent clients. [source]
• The management UI runs on port 3458 (CLI `ccr ui`, Docker), separate from the gateway on 3456; the npm CLI needs Node.js 22 or newer. [source]
• Whether CCR repairs malformed tool calls from a weak local backend is not stated in the README; its listed features are routing, retry, fallback and observability, not repair. [source]
• The README documents tool-call logging ("tool calls; agent traces" in request details), which is the only built-in aid for diagnosing translation faults. [source]
• Older guides (Dec 2025) call a translation proxy mandatory for Claude Code on local models; local-llm-server-as-a-coding-agent-backend-on-mac.md already resolves this by date. CCR's own README no longer frames local models as its purpose, so the "proxy needed" argument now rests on third-party guides only. [source]
• Exact transformer behavior for `tool_use` / `tool_result` blocks against llama-server or Ollama backends (source code not read; docs site ccrdesk.top not fetched). [source]
• Whether CCR hoists non-leading system messages (see anthropic-compatible-local-endpoints-and-role-system-messages.md). [source]
• CCR's README describes it as "a local model gateway and control plane for coding agents" giving agents one stable local endpoint. [source]
• The default CCR gateway address is http://127.0.0.1:3456. [source]
• The CCR management UI is served on http://127.0.0.1:3458 by the npm CLI (`ccr ui`) and by Docker. [source]
• The npm package is `@musistudio/claude-code-router` and requires Node.js 22 or newer. [source]
• The README lists supported protocols as OpenAI Chat / Responses, Anthropic Messages, Gemini Generate Content / Interactions, plus custom compatible providers. [source]
• CCR's provider setup includes protocol probing, model discovery and connectivity checks for custom endpoints. [source]
• CCR routing supports header and body conditions, prefixes, rewrites, retries and ordered fallback models. [source]
• CCR lists ten agent clients: Claude Code, Claude Design, Codex, Grok CLI, Kimi CLI, Kilo Code, OpenCode, Pi, ZCode and WorkBuddy. [source]
• As of 2026-10-04 the repository shows 37.5k stars, 953 commits and release v3.1.1 dated 2026-09-16. [source]
• CCR request logs record resolved provider, model, credential, status, latency, tokens, estimated cost, tool calls and agent traces. [source]
• The README does not describe any tool-call repair step; documented resilience features are retries, credential pools and fallbacks. [source]