Topic
X402
3 posts on x402, guides and lab notes from real runs on hardware we own. New posts land here automatically. Start anywhere, or grab the copy-paste prompts that ship with them.
- 3 min read
HTTP 402 Payment Required Explained: RFC 9110 + x402 V2 (2026)
Got a 402 from an API? RFC 9110 reserves the code but defines no way to pay. What HTTP 402 Payment Required means, how x402 V2 uses it (PAYMENT-REQUIRED, PAYMENT-SIGNATURE), and the V1 vs V2 headers.
- 5 min read
Why API keys break for autonomous AI agents
Stripe doesn't ship to LLMs. Every vendor signup form assumes a human at the door. Here is what changes when wallets become the access primitive.
- 4 min read
I built a memory API that AI agents can pay for
An LLM just paid me $0.001 to remember something. The agent has no account, no API key, no credit card. It just signs a USDC transfer and gets back a 200.
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