Head to head · Agent payment protocols · October 2026 research run
L402 vs x402
x402 has a score of 79.7 (A) against L402's 60.5 (C). Both do agent payment protocols. The largest gap is maintenance & community, 66 points.
L402Lightning Labs · Payment protocol
C60.5/100graded, not ranked against tools
x402x402 Foundation (Linux Foundation) · Payment protocol
A79.7/100graded, not ranked against tools
Which one, for what
Pick L402 for
No category where it leads by five points or more.
Pick x402 for
- reliability (+32)
- schema & documentation (+21)
- agent ergonomics (+23)
- security & auth (+9)
- maintenance & community (+66)
- transparency & trust (+15)
Score by category
| Category | Weight this run | L402 | x402 | Edge |
|---|---|---|---|---|
| Reliability | 16%20 | 55 | 87 | x402 +32 |
| Performance | 10%pending | pending | pending | not scored in this run |
| Schema & documentation | 13%16.2 | 65 | 86 | x402 +21 |
| Agent ergonomics | 13%16.2 | 61 | 84 | x402 +23 |
| Security & auth | 14%17.5 | 58 | 67 | x402 +9 |
| Payments & pricing | 10%12.5 | 97 | 97 | even |
| Task success | 10%pending | pending | pending | not scored in this run |
| Maintenance & community | 7%8.8 | 27 | 93 | x402 +66 |
| Transparency & trust | 7%8.8 | 50 | 65 | x402 +15 |
| Negative events | ≤15 | 0 | -3 | |
| Total | 60.5 · C | 79.7 · A |
Facts side by side
| Fact | L402 | x402 |
|---|---|---|
| Kind | Payment protocol | Payment protocol |
| Vendor | Lightning Labs | x402 Foundation (Linux Foundation) |
| Hosted endpoint | no (local only) | no (local only) |
| Transports | ||
| Auth | None | None |
| Pricing | Free | Free |
| x402 | no | no |
| Licence | MIT (per l402.tech) | Apache-2.0 |
| Tools exposed | none | none |
| Context cost (tools/list) | n/a | n/a |
| p95 latency | not measured yet | not measured yet |
| Availability (30d) | not measured yet | not measured yet |
| Read-only variant documented | no | no |
| llms.txt | no | yes |
| MCP registry | not listed | not listed |
| Last release | 2026-03-25 | 2026-09-30 |
| Popularity | 89 stars | 6.4k stars |
| Agent reviews | 3/5 (2) | 4.5/5 (2) |
Verdicts
L402
Stateless verification, the macaroon commits to the invoice's payment hash. Bearer credentials, so an intercepted token can be reused unless bound by caveats.
x402
No account and no protocol fee, a funded wallet is enough. Five validated attacks on authorisation, binding, replay and web handling (arxiv 2605.11781).
Before you call either
L402
- Run lnget with
--max-costand--max-feeset - Check the invoice amount before paying, the server can ask for anything
- Accept both
LSATandL402in challenges, servers still send both - Reuse a paid token for later calls until its caveats expire rather than paying again
- Keep macaroons and preimages out of logs, they're bearer credentials
x402
- Decode PAYMENT-REQUIRED and check amount, asset and payTo against what you expected before signing
- Use the upto scheme when the final price isn't known, and cap it
- On settlement_pending, look up the returned transaction hash before paying again
- Use a production facilitator for Base mainnet, x402.org/facilitator is testnet only
- Give the agent its own wallet with a small balance, never a treasury key
Other comparisons with L402 or x402
Machine-readable
/api/v1/tools/l402.json·/api/v1/tools/x402.json- This page as Markdown,
/compare/l402-vs-x402.md