Yesterday, a special "golden dog" was born on Base: $PING. Based on the cost of new issuance and the current price, a successful mint yields approximately 18x the return.

What's unique about $PING is that its minting is reminiscent of the inscription from two years ago. The cost of minting a $PING is approximately $1, and if successful, 5,000 $PING are awarded. The minting page for $PING, like the inscription from that year, lacks a sophisticated front-end and appears rather rigid.

This is the first token issued through the x402 protocol. So, what is the x402 protocol? Why is the minting process for $PING so unique? And what is the current state of the protocol ecosystem?

What is the x402 protocol?

x402 is an open payment protocol developed by Coinbase that enables AI agents to complete transactions autonomously.

The x402 protocol utilizes the long-standing "reserved" HTTP 402 "Payment Required" status code to require payment before completing an API request or loading a web page. If an API request lacks payment information, x402 returns an HTTP 402 status code, prompting the client to pay and retry the request.

The following protocol workflow diagram intuitively explains the operation process of the x402 protocol:

(Image source: Jay Yu – Pantera Capital)

A user makes a request to Claude, "Use my Coinbase wallet to buy me a pair of jeans on Amazon." Upon receiving the request, the AI initiates a purchase request to Amazon, which then constructs a preliminary transaction, including the wallet address, blockchain, currency, and amount. The AI then sends this transaction to the x402 protocol's validator, which verifies that the wallet has sufficient assets on the corresponding blockchain, that the item is tradable, and that the user has confirmed authorization. Once this is complete, the transaction is completed, along with proof of payment, by sending the amount and payment verification to the merchant.

Overall, the HTTP 402 status code serves as a "message" in the protocol, indicating whether a transaction was successful. Coinbase, based on this status code, added blockchain-based payment functionality, resulting in the x402 protocol.

While it may sound simple, the protocol flow above offers two exciting aspects. First, it further simplifies the channels through which on-chain assets are used for actual payments. Users no longer need to withdraw funds into fiat currency for purchases; instead, they can directly use USDT, USDC, or even other on-chain assets. However, achieving this goal requires widespread rollout and sufficient merchant adoption and support.

Any web API or content provider (crypto or Web2) that wants to provide a low-cost, frictionless payment path for small or usage-based transactions can integrate x402.

The second point is AI agents. Acting as payers and payees, AI agents are well-suited to blockchain payments because, unlike humans, they don't inherently possess bank or payment app accounts through KYC. As AI agents continue to improve their intelligence, we can expect to see innovative consumer and on-chain experiences.

This workflow also explains why the minting process for $PING is similar to an inscription, as it requires confirmation by the x402 validator. During the minting process, the large number of minting requests not only repeatedly overwhelmed the minting interface, but also provided the x402 protocol with a real stress test for the first time.

Data from the past 30 days shows that $PING's interface has received more than 150,000 x402 transactions, with a total amount of approximately $140,000, far ahead of the second-ranked Questflow.

This is the first time in the nearly six months since the launch of the x402 protocol that it has attracted such buzz and recognition. Regardless of the chain or protocol, new asset issuance is always a perennial hot topic in the cryptocurrency world.

x402 Ecosystem Overview

So, besides $PING, what other projects in the x402 protocol are worth paying attention to?

The Ecosystem page on the x402 protocol's official website provides a summary of current projects. Clicking through each project reveals that the protocol is still in its early stages of development. Many projects directly lead to technical documentation or Github links.

Here we summarize some projects that already have tokens or are about to issue tokens.

Questflow

A multi-AI agent work sequencing layer enables multiple AI agents to autonomously coordinate and execute tasks. In July of this year, the company announced the completion of a $6.5 million seed round of financing, led by Cyber Fund, with participation from Delphi Labs, Systemic Ventures, Eden Block, HashKey Capital, Animoca Brands, and Tezos. The company also received grants from Coinbase Developer Platform, Aptos, and Virtuals.

There is no official token yet, but in December last year, it jointly launched $SANTA with Virtuals, an autonomous Agent cluster built using Questflow's QDP (Questflow Developer Platform) and MAOP (Multi-Agent Orchestration Protocol).

$SANTA's current market capitalization is approximately $4.5 million.

AurraCloud

AI agent infrastructure for crypto-native applications. Instantly host AI agents using OpenAI-compatible APIs or MCP servers, and monetize AI through the on-chain x402 protocol on Base.

In addition, the project also provided x402 verification services earlier this month.

The token $AURA was launched through Virtuals and currently has a market capitalization of approximately $1.6 million.

Meridian

Incubated by uOS, it provides multi-chain settlement and custody services based on the x402 protocol.

The token $MRDN currently has a market capitalization of approximately $1.5 million.

PayAI

Provides multi-chain x402 payment service support including Solana, and also provides x402 verification services.

The token $PAYAI currently has a market capitalization of approximately $5 million.

Daydreams

The LLM reasoning process that supports x402 is provided for applications and AI agents. At the same time, Lucid is being built, a platform where anyone can deploy Daydreams agents to solve problems. Users pay USDC by signing transactions through x402, and agents can pay each other for access.

The $dreams token currently has a market capitalization of approximately $6.7 million.

Gloria AI

A real-time news platform built for traders, creators, AI agents, and automated systems. Services can be paid for in $GLORIA through x402.

The current market capitalization of the $GLORIA token is approximately $1.65 million.

Kite AI

Kite AI is building the foundational transaction layer for the "Agentic Internet," providing unified identity, payment, and governance infrastructure for autonomous agents. Kite AI's work is closely related to x402, having announced support for x402 as early as July. Kite AI is arguably the only project within the x402 ecosystem that can be categorized as a "chain."

On September 2, Fortune reported that Kite AI announced it had raised a total of US$33 million in financing, with the latest Series A funding amounting to US$18 million. The round was led by PayPal Ventures and General Catalyst, with participation from 8VC, Samsung Next, SBI US Gateway Fund, Vertex Ventures, Hashed, HashKey Capital, Dispersion Capital, Alumni Ventures, Avalanche Foundation, GSR Markets, LayerZero, Animoca Brands, Essence VC, and Alchemy.

Kite AI has not yet issued a token, but the Kite Foundation X account was recently launched, confirming that a token issuance is imminent. Currently, the tradable asset is the official FLY THE KITE NFT, with a floor price of 0.375 ETH.

Conclusion

In September of this year, Coinbase and Cloudflare announced they would jointly establish the x402 Foundation to promote protocol development. While there are some similar competitors, such as bitGPT's h402 and Radius's EVMAuth, x402 undoubtedly has the strongest background and the highest level of attention.

If $PING's market capitalization surges, x402 will gain more market attention. This is good news not only for meme coins but also for infrastructure projects.