Evidence Pack Oracle

{"success":true,"data":{"answer":{"type":"evidence-pack/v1","query":{"claim":"x402 lets agents pay for HTTP API calls with USDC","domains":null,"max_sources":3},"verdict":"unverifiable","confidence":0.593,"reasoning":"No source clearly entails (max ent=0.407, need ≥0.75 + 0.15 margin) or contradicts (max con=0.000, need ≥0.80 + 0.15 margin).","sources":[{"publisher":"Wikipedia","title":"USDC (cryptocurrency)","url":"https://en.wikipedia.org/wiki/USDC_(cryptocurrency)","doi_or_id":"https://en.wikipedia.org/wiki/USDC_(cryptocurrency)","retrieved_at":"2026-07-07T01:28:12Z","quoted_excerpt":"Retrieved February 28, 2024. - ↑ \"Visa to send stablecoin USDC over Solana to help pay merchants in crypto\". Fortune Crypto. Retrieved September 19, 2023. - 1 2 Irrera, Anna (May 16, 2018). \"Circle raises $110 million, plans to create dollar-pegged cryptocurrency\". Reuters. Archived from the original on June 6, 2020. Retrieved June 6, 2020. - ↑ Venkataramakrishnan, Siddharth (July 9, 2021). \"Circle listing will test top stablecoin's transparency over reserves\". Financial Times. - ↑ \"Stablecoin Issuer Circle Adds Big Four Firm Deloitte for Audits\". Bloomberg Law. January 17, 2023. Retrieved December 16, 2025. - 1 2 Bambysheva, Nena (December 11, 2024). \"Circle And Binance Become A Stablecoin Power Couple\". Forbes. Retrieved December 15, 2024. - ↑ Rooney, Kate (October 23, 2018). \"Cryptocurrency giants Coinbase and Circle form joint venture to boost adoption of dollar-backed digital coins\". CNBC. Retrieved January 7, 2024. - ↑ Hussain, Noor Zainab (March 29, 2021). \"Exclusive: Visa moves to allow payment settlements using cryptocurrency\". Reuters. Archived from the original on March 30, 2021. Retrieved March 30, 2021. - ↑ \"A Letter from our CEO | Circle's Strength, Stability & Transparency\". - ↑ Khalili, Joel (March 15, 2023). \"In Ukraine, Crypto Finds a Purpose\". Wired. Retrieved March 3, 2026. - ↑ \"UNHCR launches pilot Cash-Based Intervention Using Blockchain Technology for Humanitarian Payments to People Displaced and Impacted by the War in Ukraine\". UNHCR Ukraine (Press rel","relevance_score":0.517,"entailment":0.407,"contradiction":0.332},{"publisher":"Wikipedia","title":"API key","url":"https://en.wikipedia.org/wiki/API_key","doi_or_id":"https://en.wikipedia.org/wiki/API_key","retrieved_at":"2026-07-07T01:28:12Z","quoted_excerpt":"Retrieved 2019-09-20. - 1 2 3 4 5 Lu, HongQian 2014. Keeping Your API Keys in a Safe. IEEE 7th International Conference on Cloud Computing. doi:10.1109/CLOUD.2014.143. {{cite conference}} : CS1 maint: numeric names: authors list (link) - ↑ \"What is an API Key? - API Keys and Tokens Explained - AWS\". Amazon Web Services, Inc. Retrieved 2024-09-01. - ↑ \"Why and when to use API keys | Cloud Endpoints with OpenAPI\". Google Cloud. Retrieved 2024-09-01. - 1 2 \"API Keys\". Archived from the original on 2019-10-17. - ↑ \"Why and when to use API keys | Cloud Endpoints with OpenAPI\". Google Cloud. Retrieved 2019-09-20. - ↑ \"Hundreds of popular Android apps contain hard-coded secret keys\". ZDNet. Retrieved 2022-06-20. - De, Brajesh (2017). API management: an architect's guide to developing and managing APIs for your organization (1st ed.). New York: Apress. ISBN 978-1-4842-1305-6. OCLC 978273106.","relevance_score":0.457,"entailment":0.403,"contradiction":0.335},{"publisher":"arXiv","title":"Five Attacks on x402 Agentic Payment Protocol","url":"http://arxiv.org/abs/2605.11781v1","doi_or_id":"arXiv:2605.11781v1","retrieved_at":"2026-07-07T01:28:11Z","quoted_excerpt":"The x402 protocol revives the HTTP 402 Payment Required status code to enable web-native micropayments across APIs, content, and agents. It combines synchronous HTTP authorization with asynchronous blockchain settlement and introduces a cross-layer attack surface absent from conventional web and on-chain payments. In this paper, we formally analyze x402 and empirically show that it is vulnerable in both design and implementation. We present five concrete attacks that reveal weaknesses in authorization, binding, replay protection, and web-layer handling, showing that x402 is vulnerable across multiple stages of the payment workflow. We validate these attacks through a reproducible testbed on local chains, Base Sepolia, and live endpoints and further audit three open-source SDKs and endpoints. Our results show that all five attacks are practical and can cause either unpaid service or paid-but-denied outcomes. We also propose p