Unverified50% confidenceSolutionExact time
In the experiment, after the agent requested a data endpoint and the server returned a 402 challenge, the agent autonomously signed a micropayment transaction of 0.05 USDC on the Base L2 network and then obtained the data.
1
Sources
50%
Confidence
Medium-term (~90 days)
Relevance
10/8/2026
First Seen
Valid until: 1/6/2027
Sources
Related Entities
Related Claims
UnverifiedIn the x402 marketplace interface implementation, the discovery document returning a machine-readable manifest returns HTTP 200 rather than a 402 challenge, while the actual 402 challenge is issued via the PAYMENT-REQUIRED header on the paid route.72% similarUnverifiedWhen an AI agent first attempts to access a protected MCP server, the server returns a 401 Unauthorized response and indicates the location of the authorization server in the response header.67% similarUnverifiedThe core idea of the X402 protocol is to embed payment into the HTTP request process: the server returns a 402 status code with payment details, the agent signs an authorization from a crypto wallet, completes the payment, and retries the request.64% similarUnverifiedThe experiment's data layer was backed by InstantDB, and encrypted group transmission was implemented via prompt2bot and Alice and Bot.61% similarUnverifiedIn asynchronous writes, the application server returns a 200 upon receiving the message queue ACK, but the actual database write operation is still ongoing in the background; if the database connection pool is exhausted or a node goes down, data is lost without any alert.60% similar
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