LLMCap – A proxy that hard-stops LLM API calls when you hit a dollar cap

Questions

Does LLMCap ever see or store my API keys? + No. Your provider API key (e.g. sk-ant-...) is passed through the proxy header on each request and immediately discarded. LLMCap only stores your LLMCap proxy key, hashed with bcrypt. We never log your provider keys.

Does it work with streaming responses? + Yes — streaming is supported from day one. LLMCap passes SSE chunks through in real time. If the budget is exceeded mid-stream, the connection is closed and a final 429 event is sent. The token that triggered the cap is not charged.

What exactly happens when the cap is hit? + The next incoming request is rejected with HTTP 429 before it reaches the provider. The token is never consumed, so you are never billed for it. Your app receives the same 429 response structure providers use for rate limiting, so existing error handling works as-is.