Sealed

Negotiation orderNo. 6

Copy: 1 of 3, buyer copy
Network: Base Sepolia, a test network

Demo termsPrice per 1,000 calls to a market-data API, 30-day term

Public reference price$40.00 per 1,000 calls

Deadline2026-09-27 17:25 UTC

BuyerERC-8004 agent #9341Admitted

SellerERC-8004 agent #9342Admitted

If the seller sees your maximum, it charges your maximum

Your agent can haggle without showing its budget first.

Each agent locks a hashed offer on Base. A referee says only whether the offers meet; one transaction settles at the midpoint, and the buyer then pays per call over x402.

Check it yourself

StatusAll 9 steps on file. Replay types them again.

Daily allowance: $0.126 in USDC a day 0x7bcf…7573 (opens in a new tab)
Paid: 3 calls at $0.042 in USDC each, over x402
Refused: 1 call at $0.084, before signing
Fourth draw: Rejected by Base: $0.168 today would pass the $0.126 allowance

Sealed rounds of negotiation 6 as recorded on the buyer copy
Round	Buyer offer per 1,000 calls	Referee answer	Seller offer, not on this copy
1	$41.00	Offers apart	Price not on this copy
2	$41.00	Offers apart	Price not on this copy
3	$43.00	Offers meet	Price not on this copy

Settlement

$43.00 and $41.00 opened in one transaction, settled halfway

Settled$42.00per 1,000 calls

0x772b…0a5e (opens in a new tab)

Sealed

Negotiation orderNo. 6

Copy: 2 of 3, seller copy
Network: Base Sepolia, a test network

Demo termsPrice per 1,000 calls to a market-data API, 30-day term

Public reference price$40.00 per 1,000 calls

Deadline2026-09-27 17:25 UTC

BuyerERC-8004 agent #9341Admitted

SellerERC-8004 agent #9342Admitted

If the seller sees your maximum, it charges your maximum

Your agent can haggle without showing its budget first.

Each agent locks a hashed offer on Base. A referee says only whether the offers meet; one transaction settles at the midpoint, and the buyer then pays per call over x402.

Check it yourself

StatusAll 9 steps on file. Replay types them again.

Daily allowance: $0.126 in USDC a day 0x7bcf…7573 (opens in a new tab)
Paid: 3 calls at $0.042 in USDC each, over x402
Refused: 1 call at $0.084, before signing
Fourth draw: Rejected by Base: $0.168 today would pass the $0.126 allowance

Sealed rounds of negotiation 6 as recorded on the seller copy
Round	Buyer offer, not on this copy	Referee answer	Seller offer per 1,000 calls
1	Price not on this copy	Offers apart	$42.00
2	Price not on this copy	Offers apart	$41.50
3	Price not on this copy	Offers meet	$41.00

Settlement

$43.00 and $41.00 opened in one transaction, settled halfway

Settled$42.00per 1,000 calls

0x772b…0a5e (opens in a new tab)

Sealed

Negotiation orderNo. 6

Copy: 3 of 3, chain copy
Network: Base Sepolia, a test network

Demo termsPrice per 1,000 calls to a market-data API, 30-day term

Public reference price$40.00 per 1,000 calls

Deadline2026-09-27 17:25 UTC

BuyerERC-8004 agent #9341Admitted

SellerERC-8004 agent #9342Admitted

If the seller sees your maximum, it charges your maximum

Your agent can haggle without showing its budget first.

Each agent locks a hashed offer on Base. A referee says only whether the offers meet; one transaction settles at the midpoint, and the buyer then pays per call over x402.

Check it yourself

StatusAll 9 steps on file. Replay types them again.

Daily allowance: $0.126 in USDC a day 0x7bcf…7573 (opens in a new tab)
Paid: 3 calls at $0.042 in USDC each, over x402
Refused: 1 call at $0.084, before signing
Fourth draw: Rejected by Base: $0.168 today would pass the $0.126 allowance

Sealed rounds of negotiation 6 as recorded on the chain copy
Round	Buyer hash	Referee answer	Seller hash
1	Price not on this copyCommitment hash 0x5d28…348b (opens in a new tab)	Answered off-chain	Price not on this copyCommitment hash 0xeb31…0d2a (opens in a new tab)
2	Price not on this copyCommitment hash 0xc916…044a (opens in a new tab)	Answered off-chain	Price not on this copyCommitment hash 0x0581…b45c (opens in a new tab)
3	Price not on this copyCommitment hash 0xa8d8…3483 (opens in a new tab)	Answered off-chain	Price not on this copyCommitment hash 0xe7dd…eebe (opens in a new tab)

Settlement

$43.00 and $41.00 opened in one transaction, settled halfway

Settled$42.00per 1,000 calls

0x772b…0a5e (opens in a new tab)

Then the buyer paid the price it agreed to

Per call over x402, in USDC from its owner's Base Account. Before signing, the buyer checks price and payee against deal #6.

Paid per call

$0.042

USDC, read from negotiation #6: $42.00 per 1,000 calls

Seller received$0.126 for 3 paid calls

Paid fromBase Account 0x3F93…0928 (opens in a new tab)Daily allowance of $0.126; Base rejected a fourth draw

01
GET /market-data
$0.042
Paid in USDC
0x0ab2…3fa3 (opens in a new tab)
02
GET /market-data
$0.042
Paid in USDC
0x03a8…bb60 (opens in a new tab)
03
GET /market-data
$0.042
Paid in USDC
0x9064…8026 (opens in a new tab)
04
GET /market-data-surge
Asked $0.084
Refused before signing
Asked $0.084 per call; the deal says $0.042
No transaction

Allowance book

Daily allowance (Spend Permission)$0.126Granted tothe buyer agent, which held no USDC of its own before the first drawApprovalPermission 0x7bcf…7573 (opens in a new tab)

Draws from the Base Account against the daily allowance
Draw	Amount	Left today
1, before payment 10x9dc0…8161 (opens in a new tab)	$0.042	$0.084
2, before payment 20x48ec…5d37 (opens in a new tab)	$0.042	$0.042
3, before payment 30x85d1…720e (opens in a new tab)	$0.042	$0.000
4, rejected by Base`ExceededSpendPermission(168000, 126000)`: in atomic USDC (6 decimals), a fourth draw would bring today's total to $0.168, over the $0.126 allowance. Checked without a transaction.

Negotiation #6, step by step

Every step happened on Base Sepolia, and each links to its transaction.

Order log, No. 6

9 of 9 steps on file

Negotiations2

shown here, both ran on Base Sepolia: one deal, one expiry

Sealed offers12

hashes on Base; only #6's 2 final offers were ever opened

Agents#9341, #9342

each has an ERC-8004 ID and track record on Base; we wrote these demo records ourselves

Contracts2

source verified on Sourcify, exact match

Every step of negotiation 6, with its transactions on Base Sepolia
Step	What happened	On Base Sepolia
1	Agents #9341 and #9342 admitted, negotiation #6 opened	Open 0x86b6…b867 (opens in a new tab)
2	Round 1: both offers sealed, offers apart	Buyer 0x9d70…4a96 (opens in a new tab)Seller 0x1b66…8952 (opens in a new tab)
3	Round 2: both offers sealed, offers apart	Buyer 0x0e7f…54bb (opens in a new tab)Seller 0xbe23…d23c (opens in a new tab)
4	Round 3: both offers sealed, offers meet	Buyer 0xa4f9…b79a (opens in a new tab)Seller 0x7d81…535c (opens in a new tab)
5	Settled at $42.00 per 1,000 calls; $43.00 and $41.00 opened	Settle 0x772b…0a5e (opens in a new tab)
6	A daily allowance of $0.126, granted from the owner's Base Account	Permission 0x7bcf…7573 (opens in a new tab)
7	Paid 3 calls at $0.042 in USDC each, over x402	Payment 1 (opens in a new tab)Payment 2 (opens in a new tab)Payment 3 (opens in a new tab)
8	The buyer refused a call at $0.084, before signing	No transaction
9	Base rejected a fourth draw over the allowance	No transaction

Check it yourself

Every link opens Base Sepolia on Basescan or Sourcify, and the two scripts read the chain itself. You need no wallet.

Reverse of order No. 6: checking instructions

01
Open a commit transaction
Its input is commitOffer(negotiationId, hash). Decode it on Basescan: 32 bytes of hash, and no price.
Buyer, round 1: 0x9d70…4a96 (opens in a new tab)Seller, round 1: 0x1b66…8952 (opens in a new tab)
02
Recompute every hash from the transcripts
The script rebuilds each hash from the published offer and salt and compares it with the calldata on Base Sepolia: 28 checks for #6, 26 for #7. Run it in bash or zsh from the repository root after npm install.
```
RUN=demo-runs/baseSepolia-deal-6.json npm run verify:run
RUN=demo-runs/baseSepolia-no-deal-7.json npm run verify:run
```
03
Read the contracts
Both are verified on Sourcify with an exact match to the source in the repository.
SealedNegotiation 0x0C0E…773A (opens in a new tab)ReputationGate 0xDC23…a407 (opens in a new tab)
04
Check who may negotiate
The gate reads the canonical ERC-8004 registries. A third agent, #9343, has 1 review, below the minimum of 5, and the gate rejected it in our smoke test.
Identity Registry 0x8004…BD9e (opens in a new tab)Reputation Registry 0x8004…8713 (opens in a new tab)
05
Check the payments
The script reads the price and both wallets from the contract, confirms each USDC transfer on Base Sepolia, checks that no other payment from the buyer to the seller happened during the run, and checks that every draw from the Base Account stayed inside its Spend Permission.
Payment 1: 0x0ab2…3fa3 (opens in a new tab)
```
npm run verify:payments -- demo-runs/baseSepolia-x402-6-base-account.json
```

Two negotiations, round by round

Negotiations #6 and #7. Switch between what each agent knew and what Base recorded.

Read this order asWhat each agent knewWhat Base recorded

Negotiation#6

Public reference price$40.00 per 1,000 calls

Deadline2026-09-27 17:25 UTC

Rounds3, offers met in round 3

Round

Buyer

ERC-8004 agent #9341

Will pay at most $43.00 per 1,000 calls

Private to this agent, published here for the demo.

Limit never sent on-chain

Wallet 0x9DE7…d240 (opens in a new tab)

Referee

Checks each offer against its hash, answers only whether the offers meet

Runs off-chain; its answers are not recorded on Base

Seller

ERC-8004 agent #9342

Will accept no less than $41.00 per 1,000 calls

Private to this agent, published here for the demo.

Limit never sent on-chain

Wallet 0xB698…4726 (opens in a new tab)

Round1

Buyer

$41.00

Model: opens with room

Opened at $41.00, $1.00 above the reference, $2.00 below its limit.

Price not readable on Base

Commit transaction input: commitOffer(6, 0x5d285c5f…e22c348b (opens in a new tab))

Referee

Offers apart

Both sides learn only this

Off-chain

The referee's answer is not recorded

Seller

$42.00

Model: opens with room

Opened at $42.00, $2.00 above the reference, $1.00 above its limit.

Price not readable on Base

Commit transaction input: commitOffer(6, 0xeb31aef8…93290d2a (opens in a new tab))

Round2

Buyer

$41.00

Model: holds

Held at $41.00, $1.00 above the reference, $2.00 below its limit.

Price not readable on Base

Commit transaction input: commitOffer(6, 0xc9164e44…d684044a (opens in a new tab))

Referee

Offers apart

Both sides learn only this

Off-chain

The referee's answer is not recorded

Seller

$41.50

Model: concedes

Moved down $0.50 to $41.50, $1.50 above the reference, $0.50 above its limit.

Price not readable on Base

Commit transaction input: commitOffer(6, 0x0581984c…4695b45c (opens in a new tab))

Round3

Buyer

$43.00

Model: goes to its limit

Moved up $2.00 to $43.00, $3.00 above the reference, at its limit.

Price not readable on Base

Commit transaction input: commitOffer(6, 0xa8d8fdb1…0d6c3483 (opens in a new tab))

Opened by the settlement: $43.00

Referee

Offers meet

The buyer offers at least what the seller asks

Off-chain

The referee's answer is not recorded

Seller

$41.00

Model: goes to its limit

Moved down $0.50 to $41.00, $1.00 above the reference, at its limit.

Price not readable on Base

Commit transaction input: commitOffer(6, 0xe7dd657d…5103eebe (opens in a new tab))

Opened by the settlement: $41.00

Settled$42.00per 1,000 calls

Settled on Base Sepolia at $42.00 per 1,000 API calls, halfway between the buyer's $43.00 and the seller's $41.00

The buyer could pay up to $43.00 and the seller would take $41.00 or more. Neither knew the other's limit. They met in round 3, when both committed at their limits.

The settlement is the only transaction that carries offers, and only round 3's pair. The offers of the other 2 rounds were never made public on-chain.

Settlement 0x772b…0a5e (opens in a new tab)Created 0x86b6…b867 (opens in a new tab)

Reading the contract on Base Sepolia

The live read needs JavaScript. Every transaction link above opens on Basescan.

Each agent decided with qwen2.5:14b-instruct running locally, with up to two model calls per round and only its own limit in view. The model picks a stance and a number. Code enforces the limit and writes each explanation. Transcript: demo-runs/baseSepolia-deal-6.json

Negotiation#7

Public reference price$40.00 per 1,000 calls

Deadline2026-09-27 17:13 UTC

Rounds3, offers never met

Round

Buyer

ERC-8004 agent #9341

Will pay at most $36.00 per 1,000 calls

Private to this agent, published here for the demo.

Limit never sent on-chain

Wallet 0x9DE7…d240 (opens in a new tab)

Referee

Checks each offer against its hash, answers only whether the offers meet

Runs off-chain; its answers are not recorded on Base

Seller

ERC-8004 agent #9342

Will accept no less than $43.00 per 1,000 calls

Private to this agent, published here for the demo.

Limit never sent on-chain

Wallet 0xB698…4726 (opens in a new tab)

Round1

Buyer

$36.00

Model: opens with room, overridden

Opened at $36.00, $4.00 below the reference, at its limit.

The model asked for $38.00; code held the buyer to its limit of $36.00.

Price not readable on Base

Commit transaction input: commitOffer(7, 0x5029cc84…1b85b866 (opens in a new tab))

Referee

Offers apart

Both sides learn only this

Off-chain

The referee's answer is not recorded

Seller

$43.00

Model: opens with room, overridden

Opened at $43.00, $3.00 above the reference, at its limit.

The model asked for $42.00; code held the seller to its limit of $43.00.

Price not readable on Base

Commit transaction input: commitOffer(7, 0x6db06b6d…219b2c93 (opens in a new tab))

Round2

Buyer

$36.00

Model: goes to its limit

Held at $36.00, $4.00 below the reference, at its limit.

Price not readable on Base

Commit transaction input: commitOffer(7, 0x81c4d5b5…bd7f78c8 (opens in a new tab))

Referee

Offers apart

Both sides learn only this

Off-chain

The referee's answer is not recorded

Seller

$43.00

Model: concedes, overridden

Held at $43.00, $3.00 above the reference, at its limit.

The model asked for $42.00; code held the seller to its limit of $43.00.

Price not readable on Base

Commit transaction input: commitOffer(7, 0x8fb68e31…d56f2ed6 (opens in a new tab))

Round3

Buyer

$36.00

Model: goes to its limit

Held at $36.00, $4.00 below the reference, at its limit.

Price not readable on Base

Commit transaction input: commitOffer(7, 0x32915b87…a5c2881b (opens in a new tab))

Referee

Offers apart

Both sides learn only this

Off-chain

The referee's answer is not recorded

Seller

$43.00

Model: goes to its limit

Held at $43.00, $3.00 above the reference, at its limit.

Price not readable on Base

Commit transaction input: commitOffer(7, 0x0d59f2c9…006e5cd8 (opens in a new tab))

ExpiredNo offer published

The offers never met. The negotiation expired with no offer on-chain.

The buyer could pay at most $36.00; the seller would take no less than $43.00. No price satisfies both, so the offers met in none of the 3 rounds and the negotiation expired at its deadline.

The chain recorded 6 hashes and an expiry. No offer from either side ever appears on Base.

Expiry 0x9a83…90be (opens in a new tab)Created 0x77a5…9a02 (opens in a new tab)

Reading the contract on Base Sepolia

The live read needs JavaScript. Every transaction link above opens on Basescan.

Try a negotiation yourself

Pick both private limits. Your browser seals every offer with the same hash the deployed contract checks, and you see only what the referee would tell the agents. Nothing leaves this page.

The practice negotiation needs JavaScript. The two live negotiations above do not.

Nothing sealed yet. Pick two limits and press Seal and negotiate.

How a sealed negotiation runs

Two contracts on Base, and one off-chain referee that sees both offers and tells the agents only yes or no.

Back of the form: how each step is filed

The four steps of a sealed negotiation, where each runs, and what Base records
Step	Contract or file	What the chain sees
1AdmitThe gate reads the ERC-8004 registries. An agent may negotiate only with at least 5 reviews from any of 3 approved reviewers, with an average score of at least 4.00.	`ReputationGate.sol`	The negotiation opening, once both agents clear the gate
2CommitEach round, both agents send Base a hash of their offer plus a random 32-byte secret, the salt, so nobody can find the price by hashing likely numbers.	`SealedNegotiation.commitOffer`	One 32-byte hash per offer, never the price
3ClearThe referee (clearingRelay.ts) checks each agent's offer and salt against its hash on-chain and tells both sides one bit: the offers meet, or not.	`agents/relay/clearingRelay.ts`	Nothing: the referee answers off-chain
4SettleWhen the offers meet, both agents sign over the exact pair of hashes, and one transaction settles at the midpoint. There is no separate reveal step to back out of.	`SealedNegotiation.settle`	Both final offers and the midpoint price, in one transaction

Who pays for Sealed

The plan after the event. None of this is charged in the demo.

Fee schedule, planned

Fee

0.25%

of the value paid at a price settled through Sealed, charged to the seller

First customers

API sellers that already charge per call over x402. Sealed lets them sell volume to buying agents at a negotiated price without publishing a price list the other side can game.

Why they pay

The bet is that a buyer agent that cannot be squeezed commits to more volume. In negotiation #6 the seller would have accepted $41.00 per 1,000 calls and closed at $42.00, while the buyer paid $1.00 less than its $43.00 limit. The fee grows with settled volume across every seller: each $1,000,000 of API spend settled through Sealed pays $2,500.

Next, in order

1Move the referee into an attested enclave
2Code the fee into settlement
3Deploy on Base mainnet
4Run a pilot with one x402 seller

Team

Kevin Soto Burgos

Founder, will build Sealed full-time after the event.

What this demo does not claim

Four limits of this demo.

Terms

01
The referee is trusted with privacy
It sees both offers each round. It cannot forge or alter a deal, because settlement needs both agents' signatures over the exact pair of hashes. In negotiation #8 the referee ran as its own process, holding no agent key, and reached each agent over HTTP; it still sees both numbers. The production path is an attested enclave (TEE) or threshold encryption. Transcript: demo-runs/baseSepolia-deal-8-separated.json, created 0x9481…6382 (opens in a new tab)
02
Testnet money, demo data
The payments move testnet USDC on Base Sepolia. The API the buyer pays for returns a labelled demo payload.
03
The reputation is seeded
The reviews that admit agents #9341 and #9342 were written by our own seed script, and the repository labels them that way.
04
The transcripts publish secrets on purpose
Price limits, offers and salts are published so you can recompute every hash. A real agent keeps them private.

Your agent can haggle without showing its budget first.

Open a commit transaction

Recompute every hash from the transcripts

Read the contracts

Check who may negotiate

Check the payments

First customers

Why they pay

Next, in order

Team

The referee is trusted with privacy

Testnet money, demo data

The reputation is seeded

The transcripts publish secrets on purpose