claude-pipe

You pay $200/mo for Claude Max. Your tools (Cursor, Cline, Aider, LangChain, n8n...) all want an API key that costs extra. Why pay twice?

claude-pipe exposes your Claude Max subscription as a standard Anthropic API on localhost. Any tool that speaks the Anthropic or OpenAI API format works out of the box — streaming, web search, extended thinking included. No tokens extracted, no OAuth hacks. Just claude -p under the hood.

bunx claude-pipe

claude-pipe v0.1.0
Listening on http://127.0.0.1:4523

Anthropic API:  POST /v1/messages
OpenAI API:     POST /v1/chat/completions
Models:         GET  /v1/models

Quick test

curl http://localhost:4523/v1/messages \
  -H "content-type: application/json" \
  -H "x-api-key: anything" \
  -H "anthropic-version: 2023-06-01" \
  -d '{"model":"claude-sonnet-4-6","max_tokens":100,"messages":[{"role":"user","content":"Hello!"}]}'

Tool configuration

Cursor

Cursor uses OpenAI format. Go to Settings → Models → OpenAI API Key:

• API Key: anything (ignored by the proxy)
• Override OpenAI Base URL: http://127.0.0.1:4523/v1
• Select claude-sonnet-4-6 or claude-opus-4-6 as the model

Cline (VS Code)

Open Cline settings → Provider: OpenAI Compatible:

• Base URL: http://127.0.0.1:4523/v1
• API Key: anything
• Model ID: claude-sonnet-4-6

Continue.dev (VS Code)

In ~/.continue/config.yaml:

models:
  - name: Claude (Max)
    provider: anthropic
    model: claude-sonnet-4-6
    apiBase: http://127.0.0.1:4523
    apiKey: anything

Aider

ANTHROPIC_API_KEY=anything \
ANTHROPIC_BASE_URL=http://127.0.0.1:4523 \
aider --model claude-sonnet-4-6

Vercel AI SDK

import { createAnthropic } from "@ai-sdk/anthropic";

const anthropic = createAnthropic({
  apiKey: "anything",
  baseURL: "http://127.0.0.1:4523",
});

Or via environment variables:

ANTHROPIC_API_KEY=anything \
ANTHROPIC_BASE_URL=http://127.0.0.1:4523 \
bun run my-app.ts

LangChain

import { ChatAnthropic } from "@langchain/anthropic";

const model = new ChatAnthropic({
  modelName: "claude-sonnet-4-6",
  anthropicApiKey: "anything",
  anthropicApiUrl: "http://127.0.0.1:4523",
});

LlamaIndex

from llama_index.llms.anthropic import Anthropic

llm = Anthropic(
    model="claude-sonnet-4-6",
    api_key="anything",
    base_url="http://127.0.0.1:4523",
)

n8n

Use the HTTP Request node with:

• URL: http://127.0.0.1:4523/v1/messages
• Method: POST
• Headers: content-type: application/json, x-api-key: anything, anthropic-version: 2023-06-01

Dify

In Model Provider → Anthropic:

• API Key: anything
• API URL: http://127.0.0.1:4523

OpenAI SDK (Python/TypeScript)

Works with the OpenAI-compatible endpoint:

from openai import OpenAI

client = OpenAI(
    api_key="anything",
    base_url="http://127.0.0.1:4523/v1",
)

response = client.chat.completions.create(
    model="claude-sonnet-4-6",
    messages=[{"role": "user", "content": "Hello!"}],
)

Model aliases

| Alias | Resolves to | |---|---| | sonnet | claude-sonnet-4-6 | | opus | claude-opus-4-6 | | haiku | claude-haiku-4-5 | | gpt-4 | claude-sonnet-4-6 | | gpt-4o | claude-sonnet-4-6 | | gpt-4o-mini | claude-haiku-4-5 |

Features

| Feature | Status | |---|---| | Non-streaming | Supported | | Streaming (SSE) | Supported | | System prompt | Supported | | Web search (tools: [web_search]) | Supported | | Extended thinking | Mapped to --effort | | Multi-turn conversations | Serialized to XML | | Token usage reporting | Supported |

Limitations

These API parameters are accepted but ignored (no CLI equivalent):

• max_tokens
• temperature
• top_p / top_k
• stop_sequences
• Custom tool definitions (function calling)
• Image/document input

Prerequisites

• Claude Code CLI installed and authenticated (claude auth login)
• Bun runtime
• Claude Pro or Max subscription

How it works

Your tool (Cursor, LangChain, etc.)
    ↓ POST /v1/messages or /v1/chat/completions
    ↓
  claude-pipe (localhost:4523)
    ↓ spawn: claude -p --model X --output-format stream-json
    ↓ translate NDJSON events → SSE
    ↓
  Claude Code CLI (your Max subscription)

Disclaimer

This project uses claude -p (the official Claude Code CLI headless mode) to route API calls through your subscription.

No OAuth tokens are extracted. No authentication is spoofed. The real CLI handles all authentication.

License

MIT

If this saves you money, give it a star on GitHub.