ccgate

Transparent LLM cost proxy for Claude Code → DeepSeek API.

Tracks sessions, tokens, and spending in real-time — with zero added latency.

Quick Start

# Clone and install
cd ccgate
npm install

# Set your DeepSeek API key (used by Claude Code)
export DEEPSEEK_API_KEY=sk-your-key-here

# Start the proxy
npm run dev

Then configure Claude Code:

ANTHROPIC_BASE_URL=http://127.0.0.1:4100/v1
ANTHROPIC_API_KEY=sk-your-deepseek-key

How It Works

Claude Code ──SSE stream──▶ ccgate (localhost:4100) ──SSE stream──▶ DeepSeek API /anthropic
                                   │
                                   ▼
                            Console output
                         (JSON Lines or Pretty)

The proxy sits between Claude Code and DeepSeek, intercepting every API request:

1. Zero-latency SSE passthrough — chunks are forwarded immediately, no buffering
2. Token extraction — input/output/cache tokens are extracted from SSE events
3. Cost calculation — real-time cost based on DeepSeek pricing
4. Console logging — structured JSON Lines or colorful pretty output
5. Budget tracking — daily/monthly limits with warnings

Configuration

Variable	Default	Description
CCGATE_PORT	4100	Proxy server port
CCGATE_DATA_DIR	~/.ccgate	Data directory (SQLite future)
CCGATE_DAILY_BUDGET	5.00	Daily spending limit (USD)
CCGATE_MONTHLY_BUDGET	50.00	Monthly spending limit (USD)
CCGATE_LOG_FORMAT	pretty	pretty or json
CCGATE_UPSTREAM_URL	https://api.deepseek.com/anthropic	Upstream API

Log Formats

Pretty (default)

14:32:01 3f8a2b deepseek-v4-flash        1240 →   380  $0.000560 (session: $0.0142)
14:35:00 🟡 Budget daily: $4.23 / $5.00 ████████░░ 84.6%

JSON Lines

{"level":"info","event":"request","ts":"...","session":"3f8a2b","model":"deepseek-v4-flash","tokens_in":1240,"tokens_out":380,"cost":0.00056,"duration_ms":2340}
{"level":"warn","event":"budget","budget_period":"daily","budget_spent":4.23,"budget_limit":5.00,"budget_pct":84.6,"budget_status":"warning"}

Supported Models

Model	Input $/MTok	Output $/MTok	Context
deepseek-v4-flash	$0.30	$0.50	1M
deepseek-v4-pro	$0.42	$0.84	1M
deepseek-r1	$0.55	$2.19	128K
deepseek-v3.2	$0.28	$0.42	128K

Cache hit discount: 90% off input price.

Development

npm run dev      # Run with tsx (hot reload)
npm run build    # Compile TypeScript
npm test         # Run tests
npm start        # Run compiled JS

Architecture

src/
├── index.ts              # Entry point
├── proxy.ts              # Fastify HTTP proxy server
├── sse-interceptor.ts    # SSE Transform Stream (zero-latency)
├── config.ts             # Environment config
├── pricing.ts            # Cost calculation engine
├── logger.ts             # Structured console logger
├── sse-interceptor.test.ts   # SSE parsing tests
└── pricing.test.ts           # Cost calculation tests

pricing.json              # Model pricing config

MVP Status

• HTTP proxy (Fastify)
• SSE streaming passthrough (zero-latency)
• Token extraction from SSE events
• Cost calculation for all DeepSeek models
• Console output (pretty + JSON Lines)
• SQLite database (Phase 2)
• Session management (Phase 3)
• Budget enforcement (Phase 5)
• Terminal TUI (Phase 5)
• Web dashboard (Phase 6)
• Docker deployment (Phase 7)

License

MIT