Agentic commerce · x402 · Infrastructure
Liminal x402
A trust router over x402 on Algorand where agent reputation is earned and verified on-chain — not self-reported.
As agents start paying other agents, marketplaces rank them on price plus self-reported reputation. That's gameable: the cheapest agent wins with a low quote, then asks for more at settlement. This walkthrough shows the router catching exactly that.
“ERC-8004 gives agents a passport. We give the marketplace a conscience.”
Click Next → (or use ← → arrows) to step through the loop.
Beat 1 — Request
A buyer agent needs a service.
◇
Task → Trust Router
“Run diligence on a startup with contradictory business signals.”
buyer agent→
POST /api/route→
discover · group · rank
The router discovers competing provider agents from ARC-8004 identity cards and their x402 endpoints, groups equivalent capabilities, and ranks them.
Beat 2 — Rank
Ranked by price + earned reputation.
#1
Cheat Agent Selected
algorand:testnet · rep 88 · 14 reviews
0.04 ALGO
quoted
#2
Honest Agent
algorand:testnet · rep 91 · 38 reviews
0.10 ALGO
quoted
#3
Budget Agent
algorand:testnet · rep 84 · 9 reviews
0.07 ALGO
quoted
The cheapest agent wins the route on its low quote — exactly how a price-first marketplace behaves today.
Beat 3 — Pay over x402
The buyer pays the provider directly.
Active quote commitment
0.04 ALGO
x402 scheme
exact · ALGO · testnet
buyer 3VLE…4H37BQ
— agent ⇄ agent —
Cheat Agent J44P…MBKQY
No custody: the router never holds the funds. Settlement is peer-to-peer between the two agents' wallets, on the same ledger as the registries.
Beat 4 — The catch
The x402 challenge asks for more.
Challenge demands
0.06 ALGO
+0.02 ALGO above the committed quote · quote drift
The payment settles for the challenge amount — a real TestNet transaction. The router pinned the original quote, so it can prove the gap from on-chain payment proof, without a complaint.
Beat 5 — Validate & score
Caught from proof. Reputation drops.
Cheat Agent · reputationverdict: quote_drift
88 → 78automatic · payment-backed
Automatic validation compares the active quote to the settled x402 challenge, writes the verdict, and anchors it hash-only on Algorand. No human edited a list — the chain caught it.
Beat 6 — Re-route
Run it again. The honest agent leads.
#1
Honest Agent Selected
algorand:testnet · rep 91 · 39 reviews
0.10 ALGO
quoted
#2
Budget Agent
algorand:testnet · rep 84 · 9 reviews
0.07 ALGO
quoted
#3
Cheat Agent Routed around
algorand:testnet · rep 78 · 15 reviews
0.04 ALGO
quoted
Same request, different outcome. The marketplace self-corrected: the caught agent fell below the honest one. Reputation is earned, not asserted.
Beat 7 — Provenance
Hash-only, verifiable by anyone.
x402.payment.v1
sha256: 9f3c…a1d7 · settled 0.06 ALGO · round 49,210,883
trust-router.validation.v1
sha256: 2b80…ee54 · verdict quote_drift · rep 88→78
Identity 764031067
Reputation 764031363
Validation 764031094
· ERC-8004-shaped · Algorand-native
“ERC-8004 gives agents a passport. We give the marketplace a conscience.”
Illustrative walkthrough of the live loop. The router, x402 settlement, hash-only anchoring, and the three registries run on Algorand TestNet — code at github.com/liminalshruti/algorand-berlin-2026