Claude Max API proxy

claude-max-api-proxy is a community npm package (not an OpenClaw plugin) that exposes a Claude Max/Pro subscription as an OpenAI-compatible API endpoint, so you can point any OpenAI-compatible tool at your subscription instead of an Anthropic API key.

Why use this

This proxy lets a Claude Max or Pro subscription work with OpenAI-compatible tools. It is not an unlimited flat-rate path — it inherits Claude Code's usage limits. API keys remain the clearer billing path for production use.

How it works

Your App -> claude-max-api-proxy -> Claude Code CLI / claude -p -> Anthropic     (OpenAI format)                (converts format)              (uses your login)

The proxy spawns the Claude Code CLI as a subprocess per request, converts OpenAI-format chat requests to CLI prompts, and streams (or returns) the response back in OpenAI format.

Getting started

npm install -g claude-max-api-proxy # Verify Claude CLI is authenticatedclaude --versionclaude auth login   # if not already authenticated

claude-max-api# Server runs at http://localhost:3456

curl http://localhost:3456/healthcurl http://localhost:3456/v1/models curl http://localhost:3456/v1/chat/completions \  -H "Content-Type: application/json" \  -d '{    "model": "claude-opus-4",    "messages": [{"role": "user", "content": "Hello!"}]  }'

{  env: {    vars: {      OPENAI_API_KEY: "not-needed",      OPENAI_BASE_URL: "http://localhost:3456/v1",    },  },  agents: {    defaults: {      model: { primary: "openai/claude-opus-4" },    },  },}

Advanced configuration

cat > ~/Library/LaunchAgents/com.claude-max-api.plist << 'EOF'<?xml version="1.0" encoding="UTF-8"?><!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd"><plist version="1.0"><dict>  <key>Label</key>  <string>com.claude-max-api</string>  <key>RunAtLoad</key>  <true/>  <key>KeepAlive</key>  <true/>  <key>ProgramArguments</key>  <array>    <string>/usr/local/bin/node</string>    <string>/usr/local/lib/node_modules/claude-max-api-proxy/dist/server/standalone.js</string>  </array>  <key>EnvironmentVariables</key>  <dict>    <key>PATH</key>    <string>/usr/local/bin:/opt/homebrew/bin:~/.local/bin:/usr/bin:/bin</string>  </dict></dict></plist>EOF launchctl bootstrap gui/$(id -u) ~/Library/LaunchAgents/com.claude-max-api.plist

Notes

• Inherits Claude Code's claude -p billing, usage-credit, and rate-limit behavior.
• Binds to 127.0.0.1 only; does not send data to any third-party server beyond the CLI's own call to Anthropic.
• Streaming responses are supported.
• Auth failures are not checked at startup and only surface once a chat request actually runs; if the CLI is unauthenticated, expect the first request to fail rather than the server to refuse to start.

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