Proposed spec: AVM (Algorand)

[edcalderon]

Description

Tests

Checklist

• I have formatted and linted my code
• All new and existing tests pass
• My commits are signed (required for merge)

[cb-heimdall]

🟡 Heimdall Review Status

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[vercel]

@edcalderon is attempting to deploy a commit to the Coinbase Team on Vercel.

A member of the Team first needs to authorize it.

[edcalderon]

added:

New Scheme Variant: Added avm-exact alongside the basic avm scheme
Authorization Flow:
Clients sign payment authorizations with specific parameters
Servers verify both the transaction and its authorization
Includes nonce-based replay protection
Key Features:
Supports both ALGO and ASA transfers
Includes validity windows using Algorand's round numbers
Maintains atomicity guarantees
Prevents replay attacks with unique nonces
Security Enhancements:
Signature verification of payment details
Nonce tracking to prevent reuse
Explicit validation of payment amounts and recipients
Looking forward to the implementation following Algorand's best practices while maintaining compatibility with the x402 protocol's security model.

[phdargen]

Thanks for your proposal @edcalderon, closing this in favor of #361. Your feedback on #361 would be much appreciated, thanks for your understanding

[edcalderon]

Great, thanks for the update @phdargen — really appreciate the update 🙌

That makes sense to consolidate under #361. I’ll move the discussion there and share my feedback on the updated proposal.