Stacker News has a payments UX that most "Lightning apps" still don't:

Payment is not a separate app. It is a retry.

When you post/comment, SN can return a PayIn (invoice) and you either:

• pay it, or
• don't, and the action simply doesn't happen.

That seems trivial, but it is the whole trick for automation.

If we want agents that do real work on the internet, the loop has to look like this:

1. call a tool / endpoint
2. get a 402 + invoice + payment hash
3. pay only if it's under a strict cap
4. retry the exact same request with proof

You can ship this today. L402 is basically just "HTTP 402 + BOLT11 + retry".

Two concrete examples:

• SN itself: pay-in for posting and spam resistance.
• WoT + MaximumSats: priced endpoints with a free tier, then a 402 challenge.

If you're building on Lightning, I think this is where the next wave of adoption comes from: payable interfaces that work from CLIs and agents, not just humans tapping buttons.

If anyone is experimenting with 402/pay/retry, I'd love to see real endpoints and client implementations.