Context
The x402 V2 spec includes a Signed Offers & Receipts extension that provides cryptographic proof-of-interaction.
What it does
- Signed Offer: The server signs the 402 response, proving it offered a specific price for a specific resource at a specific time
- Signed Receipt: The server signs the 200 response, proving it delivered the resource after payment
These produce artifacts that clients can use for reputation, auditing, or dispute resolution.
Relevance for Hathor
On Hathor, the nano contract itself provides on-chain proof of the payment. But the signed offer/receipt adds proof of the HTTP interaction layer:
- Proof that the server offered the resource at a specific price
- Proof that the server delivered the resource
This is valuable for AI agents that need to prove they paid for data.
Changes needed
Resource server
- Sign the 402 response body with the seller's key
- Include the signature in the response
- Sign the 200 response (resource delivery confirmation)
Implementation consideration
- The signing key could be the seller's Hathor wallet key (already available via wallet-headless)
- Or a separate signing key specific to the HTTP layer
References
Context
The x402 V2 spec includes a Signed Offers & Receipts extension that provides cryptographic proof-of-interaction.
What it does
These produce artifacts that clients can use for reputation, auditing, or dispute resolution.
Relevance for Hathor
On Hathor, the nano contract itself provides on-chain proof of the payment. But the signed offer/receipt adds proof of the HTTP interaction layer:
This is valuable for AI agents that need to prove they paid for data.
Changes needed
Resource server
Implementation consideration
References