Yeah that's a good way to put it. Starting with the proxy feels safe because there's no code change.
But what happens when you suddenly need to track costs for a specific feature or customer segment six months from now? With the proxy, you can't go back and slice the data, right? You'd have to switch tools and start over.
So the "overkill" now might save a huge headache later? Or am I overthinking it?
You stopped mid-sentence, but you're right about the architectural distinction. It's not just about "comprehensive vs lightweight." The core difference is telemetry push vs proxy pull.
Langfuse requires you to push structured data on your terms. Helicone's proxy pulls it from your request/response stream. That initial choice dictates what's possible later. With push, you can attach any business context you want at the source. With pull, you're limited to what's in the HTTP headers and body.
The data portability argument for Helicone is valid, but only if you never need to query by anything beyond user ID or API key. The moment you need cost per feature or customer tier, that "portable log" is useless.
Metrics don't lie.