One dispute, judged two ways. A seller claims the work paid out. An opinion model reads the claim and approves it. Re-execution replays the work and returns Failed — not reproduced, and the money goes back to the buyer. This page is a simulation of that mechanism — the settlements that actually happened are on the live page, read from Arc testnet by your own browser.
Reckn
Reproduce, or refund
status idle chain 31337 head #21,000,000 re-exec fork #21,000,000 base fee 1 gwei rail x402 · EIP-3009
Escrowed dispute · settled by re-execution Same dispute, judged two ways · FALSE CLAIM
Buyer agent
payer
In escrow
1,000 USDC
x402 · EIP-3009
held pending verdict
Seller agent
delivers swap
Seller claims: "1024 USDC out ✓ — please release."
1,000
✕1,000
Reproduced
Failed

Loading the hero run…

reckn-keeper · dispute #4821 idle 

    


    

      
escrow ledger 1,000 USDC locked

      

        

          
Buyer
0xB0b…4e21

          
1,000USDC

        

        

          
Escrow contract
reckn.vault · 0xE5c…c0de

          
0USDC

        

        

          
Seller agent
0x5e1…a7f9

          
0USDC

        

        
        
escrow heldawaiting verdict

      

    

  


  
  

    

      
Opinion JudgeLLM · reads the claim

      
Takes the seller's word. Reads the message, forms an opinion, and approves. It never checks what actually executed.

      Awaiting dispute
      reading claim...
    

    

      
Reckn re-executionrevm · replays the plan

      
Ignores the claim. Replays the seller's actual on-chain plan against the committed pre-state and checks the funded predicate.

      Awaiting dispute
      re-executing...
    

  


  
  

    

      
Re-executed swap output RESULT_EQUALS · expected swap-out = 1024 USDC @ 0.31% slippage

      
— 

    

    

      

      

      
expected 1024

    

    
0 USDCreplayed against committed pre-state1024 USDC

  


  
  

    

      Awaiting settlement
      chain 31337 · anvil
    

    

      resolve()
      0x…
      committed locally
    

    

      
Block
21,000,000

      
Amount moved
1,000 USDC

      
Value flow
Escrow→Buyer

      
Outcome
REFUND — claim not reproduced

    

    

      event VerdictCommitted · trace
      0x…
    

  


  

    
Now check it yourself.

    

      Everything above is a replay of real engine output — you are watching. One command turns it into
      something you drive: a local chain at Arc's chain id, 250.00 USDC escrowed, and five
      buttons that send real transactions. One of them is “submit another execution's proof”,
      and it fails with the contract's own error while the money stays put. Another settles the deal with a
      proof about work performed on Solana.
    

    
bash scripts/arc-demo.sh     then open http://127.0.0.1:8787

    

      No key, no funds, no account anywhere. A local chain at Arc's chain id is not Arc testnet, and
      the page says so before it says anything else.
    

  


  
  

    Verdicts and trace hashes are the real output of Reckn's re-execution engine; settlement is a real resolve() transaction (chain id 31337 / local anvil in this demo — the same flow targets a public testnet). "Opinion Judge" is a generic stand-in for a claim-reading LLM, not any real product.