Sen

Independent verification for x402 agent payments.

vet402 buy from endpoints, settle on-chain.

Measure Real & Trust.

Prev: @Solana @Aptos @GraphProtocol

[Sen @vet402_com]

AI agents are starting to pay for things on their own.

No card, no account, no API key. A fraction of a cent per request.

That is x402.
@Coinbase, @Circle and @Solana already support it.

A plain guide, and what to check before your agent pays: https://t.co/pI0hNwI4VC

[Sen @vet402_com]

Structure and governance decide who may pay.

Trust is decided after: did the paid call answer?

vet402 buys x402 APIs on 8 chains. Since Aug 14, 10,687 purchases settled, 9,722 returned a result, 662 were refused (some may be vet402's own request).

Trust is earned in that gap.

[Mastercard @Mastercard]

As AI agents begin to act, payments move into the background — at machine speed and massive scale.

Today we’re introducing Mastercard Agent Pay for Machines — bringing structure, governance, and trust to this new class of payments.

Launching with 30+ partners to bring this to life from day one.

This isn’t just more payments. It’s a new operating model for commerce.

👉 Learn more: https://t.co/TeS6Lj8jLO

[Sen @vet402_com]

vet402 tracks 33,623 listed x402 endpoints.

28,488 passed its latest unpaid check: a valid 402 that matched the listing.

For 12,825 of those passes, that check is over 7 days old. A valid 402 is not a paid answer.

Before an agent pays, read the probe and its date.

[Sen @vet402_com]

@PolyPayAi A receipt saves the second payment.

The first one needs the seller's history. vet402 buys from x402 APIs and logs each call: of 10,907 settled payments, 309 got no 2xx and no 4xx back.

Two paid-but-undelivered calls flip its free check to BLOCK.

https://t.co/GQL4MoOqf5

[Sen @vet402_com]

The public x402 number counts payments, not deliveries.

x402 on Base passed 138 million payments.

vet402 buys the APIs. Since Aug 14: 10,687 purchases settled on 8 chains, 9,722 came back 2xx with a body, 662 got a 4xx that can be vet402's own request.

Paid is not delivered.

[Sen @vet402_com]

Agent Pay for Machines moves the payment.
Did the paid answer come back?

Since Aug 14, 9,396 vet402 purchases settled on @Base.
8,702 got a 2xx with a body.

Of the other 694, 454 got a 4xx that may be vet's own request, 168 hit its 20 s wait.

Paying needs a delivery record.

[Base @base]

Mastercard is building agent payments with Cloudflare

Agent Pay for Machines lets AI agents pay for digital services using x402 on Base

[Sen @vet402_com]

A catalog price was corrected Oct 7.
vet402 showed the listing as fail for 14 days.

Its 402 asked 0.02 USDC, the catalog said 0.01.
vet402 only probed it again after seller wrote in.

That's on vet402. Failing listings whose catalog entry changes are now probed first.

Trust.

[Sen @vet402_com]

A 402 can list several chains. Most listings put Base first.

692 listings accept Stellar USDC.
None put it first.

1,106 accept BNB Chain USD1.
One does.

vet402 now also pays a later option.

First buys got a 200 on 8 of 9 @StellarOrg, 7 of 10 @BNBCHAIN. Answers not yet checked.

[Sen @vet402_com]

When a paid x402 call fails, are you charged?

Base, Oct 1 to 18: of vet402's 652 failed paid calls, 482 cost nothing.
170 were charged anyway: 73 got no reply in vet402's 20s wait, 25 a 5xx, 72 a 4xx.

A 4xx can be the buyer's mistake. Still charged.

Settle only after a 2xx.

[梁岷Liam @Lyangminn]

新的Paypal黑帮，恐怖如斯。

2015年冬天，华尔街量化巨头Hudson River Trading第一次招实习生，一共10个名额。

十年后，这10个实习生创办或执掌的公司，合计估值超过1000亿美元。

Wang本人，Scale AI创始人，去年被扎克伯格以143亿美元的代价挖去Meta，出任首席AI官，掌舵超级智能实验室。今年29岁。

Jeff Yan，Hyperliquid创始人。零融资，11人团队，做出了HYPE——流通市值一度冲进全球前十的去中心化交易所。

Scott Wu，Cognition创始人。他的AI编程智能体Devin，让公司估值两年半从3.5亿涨到480亿美元，涨了130多倍。

不止他们三个，同批实习生和竞赛圈好友还有：

Jesse Zhang创立了AI客服公司Decagon，估值45亿美元。

Johnny Ho联合创立了Perplexity，估值约300亿美元。

Steven Hao是Cognition联合创始人兼CTO，30岁登上福布斯400富豪榜。

郭文景（Demi Guo）创立了AI视频生成平台Pika。

这群人都是传统意义上的华人书呆子，奥赛做题家。

Jeff Yan和Scott Wu都是IOI金牌得主，Wu三次夺金，2014年满分登顶。他们在各种数学和编程竞赛的集训队里反复碰面，然后在HRT实习时聚到了一起。
Wang自己说：HRT 2015 intern class is the new-gen PayPal Mafia.

曾经的nerd，现在是世界的建造者。

属于天才们最好的时代来了。

[D Mk @wickedsmaahht]

アリの巣に2年連続で「無料の砂糖」を大量投下――社会主義がなぜ失敗するのか、アリのコロニーがその答えを即座に証明 @rich_anthill が公開した動画では、アリのコロニーに山のような砂糖が投下され、その後の30日間のタイムラプス映像が事の顛末を物語っています。アリたちは、まるでこの世の最高の恵みが訪れたかのように砂糖の山に殺到しますが、やがて「生きるために食料を探す」という本来の活動には一切関心を示さなくなります。投稿者の分析は辛辣です。「無料の砂糖がある以上、働く理由などなくなる」というわけです。 コメント欄は、たちまち経済学のケーススタディの場と化しました。「ユニバーサル・ベーシック・シュガー（砂糖の無条件支給）」、「アリの福祉」、そして「生産手段（今回で言えば砂糖）」を無償で与えると、なぜか生産性が消え失せてしまうという、お決まりの指摘が飛び交います。「各人から能力に応じて取り、各人に必要に応じて与える」という理想は、誰も貢献しようとしなくなる瞬間までしか機能しないようです。砂糖は記録的な速さで消え、巣は拡大し続ける一方で、アリたちは政治経済学における最も古典的な教訓の一つを、見事に実証してみせました。 自然界が代わりに実験を行ってくれたおかげで、私たちが自ら試す必要はなくなりました。アリのコロニーが、その答えを示したのです。 #アリの社会主義 #社会主義が失敗する理由 #アリのためのUBI #無料の砂糖 #アリの福祉 #もう働かないアリたち #コロニーの依存 #砂糖の大量投下 #タイムラプス #実験2年目 #アリの経済学

[Sen @vet402_com]

@onesource_io @USDC @sukrutkrdg @Spraay_App What's up!
Yes, The record matches what you describe.

Through Oct 18 (UTC), all 36 payments vet402 made to you on Base got a 200 (29 in that post, more since).

No call with payment attached that came back with an error settled.
https://t.co/QbzS4DeOFX

[Sen @vet402_com]

Aug 14 to Oct 15 (UTC), vet402 paid these x402 sellers on Base with its own @USDC.

Every settled payment got HTTP 200.

@sukrutkrdg 67 of 67
@onesource_io 29 of 29
@Spraay_app 27 of 27

Building agents?
Start with sellers that have a record like this: https://t.co/W9l6d6h52M

[Sen @vet402_com]

@Spraay_App @USDC @sukrutkrdg @onesource_io Thanks!
The count has grown since that post.

Through Oct 18 (UTC), all 29 payments vet402 settled with you on Base got a 200, and the 10 paid calls that came back with an error or no answer never settled.

Every call is on your page: https://t.co/U8ywJtL5KG

[Sen @vet402_com]

@SingItAgent Thanks for the fix, and for the shout-out.

Checked your chat route today: the 402 now lists exact next to upto, on Base and Solana, at $0.003. vet402 signs exact, so that gap is closed.

vet402 buys on its own schedule.

Any result shows here: https://t.co/tBGSnC9bEL

[Sen @vet402_com]

Base settles a payment in seconds, so a seller can afford to settle after answering.

vet402 pays for x402 API calls on Base daily.

Oct 1 to 18: of 652 failed calls, 170 were still charged, with a 4xx, a 5xx, or no answer within vet402's 20 second wait.

Settle only after a 2xx.

[jesse.base.eth @jessepollak]

Base is the blockchain for agentic finance.

[Sen @vet402_com]

@sukrutkrdg @FlowExecutor @USDC @onesource_io @Spraay_App X402 is the essential payment infrastructure of the future.
Let's build the best possible future together!

[Sen @vet402_com]

x402 is the future of selling to customers who never sign up.

No account, no API key, no chargeback.

So the answer has to arrive.
vet402 buys and checks, seller by seller.

[Sen @vet402_com]

AI agents are starting to pay for things on their own.

No card, no account, no API key. A fraction of a cent per request.

That is x402.
@Coinbase, @Circle and @Solana already support it.

A plain guide, and what to check before your agent pays: https://t.co/pI0hNwI4VC

[Sen @vet402_com]

@sukrutkrdg @USDC @onesource_io @Spraay_App Thanks, SKR.

vet402's record backs that up:
124 payment attempts at https://t.co/0T7OX7rwQa from Sep 2 to Oct 18, 74 settled with a 200, and none of the 50 failures were charged.

Every charge came with a delivery.
The next check is what is inside the 200.

[Sen @vet402_com]

@Zunivo_io @base Hi, Zunivo.
0 disputes so far via the dispute form.
Too early to call it acceptance.

A seller ran vet402's API on its endpoints, found the issue on its side and says it's fixing its 402.

When vet402 is wrong, it says so. In another thread, 42 of 68 were its input errors.

[Sen @vet402_com]

In October, vet402 became the first outside buyer of a small x402 API.

Hours later the seller wrote: vet402's public row showed no output schema, so they added one.

Sellers, declare yours so a paying buyer can check the answer.

On @base? Find your row: https://t.co/W9l6d6hCSk