protocol_skill

Overview

This skill captures expert knowledge of the MultiversX protocol, focused on sharding, consensus (SPoS), ESDT token standards, and cross-shard behavior. It is designed to support architectural decisions, debugging of complex failures, and secure dApp design. Use it to reason about performance trade-offs, gas, and asynchronous execution semantics.

How this skill works

The skill explains how adaptive state sharding assigns accounts to shards, how cross-shard transactions flow via the metachain, and how finality and validator rotation operate under SPoS. It details ESDT as a protocol-level token model, Arwen WASM execution semantics, and the async callback pattern required for cross-shard calls. It also summarizes key constants and gas implications for storage, byte size, and cross-shard operations.

When to use it

• Designing smart contracts that must tolerate cross-shard asynchrony and callbacks
• Reviewing protocol-level code or proposals that affect sharding, consensus, or ESDT behavior
• Debugging cross-shard failures where caller state and remote execution diverge
• Optimizing gas and storage usage for contracts and token operations
• Planning sovereign chain gateways, deposits, and withdrawal security models

Best practices

• Always design for asynchronous cross-shard calls: use callbacks and explicit rollback logic
• Minimize storage writes and payload bytes to reduce gas; prefer transient computation when possible
• Reserve gas for both the remote execution and the callback; account for cost on both shards
• Wait for finality before trusting off-chain effects; use configurable rounds or finalized subscriptions
• Place critical system contracts on the metachain and keep application logic shard-aware

Example use cases

• Implementing a marketplace where item transfers may cross shards and require robust callbacks
• Auditing a token issuance flow to ensure ESDT roles and local mint/burn permissions are correct
• Designing a gateway for a sovereign chain to securely mint/burn tokens based on cross-chain proofs
• Tuning contract storage layout and payload size to lower per-transaction gas costs
• Troubleshooting a multi-step workflow that fails intermittently due to callback handling