Sigil
mock Selfie Check
01

Sigil

Every claim about an AI skill on Sigil has USDC behind it. Produce the trace that breaks the claim and the stake is yours.

02

Live from the gateway

skills listed
USDC escrowed on Arc
claims broken
paid requests
last settlement

loading…

03

How a claim dies

#stepwhat happenswhere
01ClaimA staker locks USDC in SigilStake behind one predicate about the skill: no env read, no network egress or no filesystem read outside an allowlist.Arc · openClaim
02ConsumeAn agent pays for the skill's source per call over x402. Blocky402 settles the payment in HTS USDC and a license NFT is minted to the payer.Hedera · x402, HTS
03ProbeThe agent runs the skill in a deterministic sandbox. Every env, fs and net event is logged; the canonical trace is hashed.sandbox · sha256
04DisputeA violation in the trace is evidence. The disputer posts a counter-bond of at least 25% and the trace hash on Arc; the bundle lands on HCS-1.Arc · dispute, Hedera · HCS-1
05SettleThe verifier re-runs the bundle. If the hash reproduces, resolve() pays stake and bond to the disputer; if not, to the staker.Arc · resolve, Hedera · HCS
04

Why three chains

layerchainwhy it must be there
Claim records, evidence, outcomesHedera (HCS)Sub-cent fees and 3s finality make per-event immutable writes affordable. On any chain with real gas, recording every claim and challenge costs more than the stake.
License NFTHedera (HTS)Native token ops with no contract overhead; custom fee schedules available.
Paid accessHedera (x402 via Blocky402)Mandated by the track. Per-call metering at sub-cent cost.
Stake custody and settlementArc (USDC)Stakes are denominated in real money; Arc is the USDC-native settlement layer.
Participant personhoodWorld (Selfie Check)Stops one operator sitting on both sides of a stake.
05

What is real

whatwhere
Blocky402 settlement in HTS USDC0.0.7162784@1789216091.354310097
resolve() settlement on Arc, signed by the Circle Agent Stack wallet0x05489e9d…b3d9b4
HCS claim topic with the full trail0.0.10499701
SigilStake contract on Arc testnet0x66fc6324…1566fe
Selfie Check runs as a labelled mock until World Sandbox access lands.Mock Selfie Check (World Sandbox access pending)
For developers

Everything above happens in this app. From the repo, one command runs the whole cycle the way an agent does, against Hedera testnet and Arc testnet:

E2E_FRESH_PAYER=1 POLICY_MIN_STAKE_USDC=10 POLICY_MIN_CLAIM_AGE_SEC=0 pnpm e2e

Documentation·Source on GitHub