L402 vs s402
Both belong to the HTTP 402 family group on this map. The map lists them as complementary: sites and agents commonly implement both.
| L402 L402 | s402 s402 | |
|---|---|---|
| Lifecycle step | 7 Pay: Settle the bill | 7 Pay: Settle the bill |
| Answers | How can a client pay for, and then authenticate to, a metered API resource over the Lightning Network with no accounts or database-backed sessions? | How can an agent pay a Sui-native resource using six payment schemes (including prepaid batching and escrow), while staying wire-compatible with plain x402 clients? |
| Governed by | Lightning Labs | Single open-source project (s402-protocol on GitHub); no standards body, no foundation; explicitly a 'profile' of x402 rather than a competing standards effort |
| Status (issuer's words) | Active, registered as an HTTP Authentication scheme (RFC 7235-style) | Archived repository (observed 2026-10-16) |
| Phase | living | deprecated |
| Version | current protocol-specification.md on the master branch | Wire Format Specification v1, Draft, dated March 2026 (repository has continued past this to align with x402 v2) (2026-03) |
| Form / transport | HTTP header | HTTP header |
| Found at | none — signalled per-request, no well-known file | none — no /.well-known/s402.json was found; discovery is per-request via the 402 envelope, matching x402's model |
| Adoption | unmeasured | unmeasured |
| Evidence | 2 verified | 4 verified |
| Primary use case | Accept payments from agents | Accept payments from agents |
| Last verified | 2026-10-19 (current) | 2026-10-19 (current) |
| Specification | https://raw.githubusercontent.com/lightninglabs/L402/master/protocol-specification.md | https://raw.githubusercontent.com/s402-protocol/core/main/docs/specification.md |
When to use which
- Choose L402 when your question is “How can a client pay for, and then authenticate to, a metered API resource over the Lightning Network with no accounts or database-backed sessions?” and you accept its maturity: phase living, adoption unmeasured.
- Choose s402 when your question is “How can an agent pay a Sui-native resource using six payment schemes (including prepaid batching and escrow), while staying wire-compatible with plain x402 clients?” and you accept its maturity: phase deprecated, adoption unmeasured. It is no longer maintained; prefer its successor.
Read the full articles
- L402: How can a client pay for, and then authenticate to, a metered API resource over the Lightning Network with no accounts or database-backed sessions?
- s402: How can an agent pay a Sui-native resource using six payment schemes (including prepaid batching and escrow), while staying wire-compatible with plain x402 clients?