Skip to main content
Base URL: https://api.nozle.app/api/v1 Reverse proxy routes that forward LLM requests to OpenAI or Anthropic and automatically track token usage. The proxy reads the response to extract { model, input_tokens, output_tokens, latency_ms } and fires an internal nozle.track() event — no SDK wrapper needed on your side.
LLM proxy routes use X-Nozle-Key for Nozle authentication, not the Authorization header. The Authorization header is reserved for the customer’s own LLM provider API key, which the proxy forwards untouched to the provider.

​
/api/v1/proxy/openai/v1/*

Proxies all requests to https://api.openai.com/v1/*. Any OpenAI-compatible endpoint works (chat completions, embeddings, etc.). Auth: X-Nozle-Key header (sk_ only) Required headers:
HeaderDescription
X-Nozle-KeyYour Nozle secret key (sk_live_...)
X-Nozle-CustomerExternal customer ID to bill for this usage
AuthorizationCustomer’s OpenAI API key (Bearer sk-...)
cURL
curl -X POST https://api.nozle.app/api/v1/proxy/openai/v1/chat/completions \
  -H "X-Nozle-Key: sk_live_your_nozle_key" \
  -H "X-Nozle-Customer: cust_123" \
  -H "Authorization: Bearer sk-customer-openai-key" \
  -H "Content-Type: application/json" \
  -d '{
    "model": "gpt-4o",
    "messages": [{"role": "user", "content": "Hello"}]
  }'

​
/api/v1/proxy/anthropic/v1/*

Proxies all requests to https://api.anthropic.com/v1/*. Auth: X-Nozle-Key header (sk_ only) Required headers:
HeaderDescription
X-Nozle-KeyYour Nozle secret key (sk_live_...)
X-Nozle-CustomerExternal customer ID to bill for this usage
AuthorizationCustomer’s Anthropic API key
cURL
curl -X POST https://api.nozle.app/api/v1/proxy/anthropic/v1/messages \
  -H "X-Nozle-Key: sk_live_your_nozle_key" \
  -H "X-Nozle-Customer: cust_123" \
  -H "x-api-key: customer-anthropic-key" \
  -H "anthropic-version: 2023-06-01" \
  -H "Content-Type: application/json" \
  -d '{
    "model": "claude-sonnet-4-20250514",
    "max_tokens": 1024,
    "messages": [{"role": "user", "content": "Hello"}]
  }'
The proxy returns the provider’s response unchanged. Your customer’s API key is forwarded but never stored. Token usage is extracted from the response and tracked automatically as a billing event on the llm_tokens metric.