staking-reward-streamer/docs/xp-token.md

XPToken

Overview

The XPToken is an ERC-20 token implementation with a modified supply mechanism that incorporates external reward providers. XP tokens are not transferrable, but they can be used as voting power in the Status Network.

Features

• Minting with Restrictions:
  • The contract owner (admin) can mint tokens, and their accounting is kept internally.
  • Prevents exceeding a dynamically calculated mint allowance.
• Reward Providers Integration:
  • Tracks balances and supplies from external reward providers.
  • Allows addition and removal of reward providers by the owner.
• Non-Transferrable Tokens:
  • Transfers, approvals, and allowances are disabled.
  • Users can only receive balances from minting or reward distributions.
• Supply Calculation:
  • The total supply is the sum of the internal supply and the external supplies.

Contract Details

• NAME: "XP Token"
• SYMBOL: "XP"

State Variables

• rewardProviders: A list of addresses implementing the IRewardProvider interface.

Errors

• XPToken__MintAllowanceExceeded: Raised when minting exceeds the allowed threshold.
• XPToken__TransfersNotAllowed: Raised when a transfer, approval, or transferFrom is attempted.
• RewardProvider__IndexOutOfBounds: Raised when an invalid index is used for removing a reward provider.

Supply and Balance Calculation

• totalSupply(): Sum of the internal supply and the sum of external supplies from reward providers.
• balanceOf(address): Internal balance plus the sum of external balances from reward providers.

Sources of XP Tokens

One of the sources for the generation of XP tokens is the staking protocol, with more sources planned in the future.

Notes

• The contract is designed to work alongside an external reward system.
• Transfers and approvals are explicitly disabled to enforce controlled distribution.
• The contract ensures a dynamic supply mechanism tied to external rewards.