Sui Launches Seal MPC Prototype for AI Payments Without Private Key Access

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• Mysten Labs launched the Seal MPC prototype on the Sui testnet to enable AI-driven payments without exposing private keys.
• Multi-party computation (MPC) distributes cryptographic authority across multiple parties, preventing unilateral fund access.
• On-chain Move smart contracts enforce spending policies such as transaction limits, approval requirements, and approved counterparties.
• The prototype builds on the decentralized Seal Key Server, which went live on the Sui testnet in March 2026.
• A mainnet release is anticipated around June 18, 2026, subject to testing, audits, and further development.

Sui Introduces Seal MPC Prototype for Secure AI Transactions

Mysten Labs has launched the Seal MPC prototype on the Sui testnet, introducing a framework designed to allow autonomous AI agents to initiate and manage payments without directly controlling users’ private keys.

The prototype combines multi-party computation (MPC) with on-chain policy enforcement to address a growing challenge in agentic commerce: enabling AI systems to perform financial actions while maintaining user control over digital assets.

Instead of granting an AI agent full access to a wallet, Seal MPC distributes cryptographic authority across multiple participants. Under this architecture, no single party, including the AI agent itself, can independently authorize or execute transactions.

The launch follows the deployment of the decentralized Seal Key Server on the Sui testnet around March 12, 2026. That infrastructure introduced decentralized secrets management capabilities, forming the foundation for the newly released programmable wallet prototype.

Move Smart Contracts Govern AI Spending Policies

Under the Seal MPC model, AI agents can propose transactions, but execution remains subject to predefined on-chain access controls written in Move smart contracts.

Users can establish spending policies using natural language-style rules rather than complex code. These policies can include daily spending limits, approval thresholds, and restrictions limiting payments to specific counterparties.

Once configured, the rules are automatically enforced by smart contracts on the network. This approach allows AI systems to carry out authorized actions while ensuring that transactions remain within user-defined boundaries.

The system leverages Move, the programming language used by Sui. Originally developed at Meta as part of the Diem project, Move was designed specifically for secure digital asset management and programmable ownership controls.

Seal’s decentralized secrets management architecture further reduces risks associated with centralized key storage by distributing cryptographic material across a network of key servers rather than relying on a single storage location.

Seal MPC Expands Sui’s Agentic Commerce Infrastructure

Mysten Labs has positioned Seal MPC as part of a broader infrastructure stack supporting agentic applications on Sui. Beyond payments, the technology is intended for encrypted messaging, secure enclaves, and other applications that require controlled access to sensitive information.

The prototype also complements Walrus, Sui’s decentralized storage infrastructure. Together, the technologies aim to provide developers with tools for secure transaction execution, encrypted data management, and decentralized application development without dependence on centralized service providers.

For the Sui ecosystem, additional infrastructure may expand potential blockchain activity by supporting new categories of AI-enabled applications that require automated transactions and programmable access controls.

However, Seal MPC remains a testnet prototype. Security audits, stress testing, and real-world validation are expected before broader production deployment. The anticipated mainnet rollout around June 18, 2026, represents the next milestone in the project’s development roadmap.

The prototype was built using a Move 2024 package and React dapp-kit, providing developers with a reference architecture for building AI-powered applications that require secure and policy-controlled blockchain interactions.

Recently, Sui launched its Confidential Transfers Beta, introducing privacy-enhancing transaction capabilities designed to support regulatory compliance and institutional use cases. At the same time, the network experienced three mainnet outages within two days following the v1.72 upgrade, raising concerns about operational stability. The developments reflect Sui’s ongoing push to expand blockchain privacy while addressing infrastructure reliability after recent upgrades.