Mysten Labs and Google Cloud Unveil Verifiable Agent Arbiter

PALO ALTO, Calif., Oct. 6, 2026 /CourierPR/ -- Mysten Labs, in collaboration with Google Cloud, has unveiled a new system called Verifiable Agent Arbiter (VAA). This innovative solution aims to provide enterprises with a reliable and neutral record of their AI agents' actions, ensuring that these agents operate within the boundaries of their granted authority.

VAA works by separating the record of an agent's activity from the proof of its integrity. Detailed telemetry, including prompts, model outputs, tool calls, and policy decisions, remains private in customer-controlled Google Cloud Storage. Cryptographic proofs of this record are stored on Walrus, the data platform designed for the demands of AI, and coordinated on Sui, a Layer 1 blockchain.

One of the key capabilities of VAA is its ability to facilitate dispute replay across companies. When two organizations' agents transact through the open Agent2Agent (A2A) protocol, developed by Google Cloud and donated to the Linux Foundation, both parties can replay a disputed workflow against the same verifiable receipts. This allows them to establish what was committed, what was delivered, and where it failed, in minutes rather than days spent reconciling conflicting logs.

Security teams can also use VAA to reconstruct the instructions, policies, decisions, outputs, and tool actions surrounding a suspected rogue execution. This helps distinguish between various types of incidents, such as a prompt-injection attack, a policy bypass, a model failure, and a post-incident change to the logs.

Another significant feature of VAA is its ability to provide a durable record retention. Archived evidence can be re-proven under future cryptographic standards, including post-quantum, without breaking its link to the original record. This ensures that the integrity of the records remains intact even as technology evolves.

VAA also integrates directly with the Sui Agent Payments facilitator, allowing agents to discover services and settle payments for API calls instantly using the x402 protocol. VAA cryptographically logs the underlying authorization, spend decisions, and service delivery, providing a secure and transparent transaction process.

Evan Cheng, Co-Founder and CEO of Mysten Labs, emphasized the importance of VAA in ensuring that AI agents do not exceed their authority.

Initial deployments with enterprise customers are planned ahead of broader availability. The system is designed to meet upcoming regulatory requirements, including the EU AI Act, which from 2027 will introduce penalties of up to €15 million or 3% of global annual turnover for logging failures.

Mysten Labs, founded by the core team behind Meta's first stablecoin initiative, is the original contributor to Sui, the Layer-1 blockchain where money moves as freely as messages, and to Walrus, the data platform built for the demands of AI. The company continues to push the boundaries of blockchain technology and AI integration, providing robust solutions for the evolving landscape of autonomous agents.