> For the complete documentation index, see [llms.txt](https://docs.useprecursor.xyz/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.useprecursor.xyz/resources/references.md). # References External standards, network documentation and infrastructure that Precursor builds on. Precursor is built on open standards and public infrastructure. These are the external sources behind the conventions these docs use. ## Robinhood Chain | Resource | What it covers | | ------------------------------------------------------------------------------------ | -------------------------------------------------------------------------------------------------------------------------------------------------------------- | | [Connecting to Robinhood Chain](https://docs.robinhood.com/chain/connecting) | Chain IDs, RPC endpoints, sequencer feeds and the block explorer for mainnet and testnet | | [Add network to your wallet](https://docs.robinhood.com/chain/add-network-to-wallet) | Wallet configuration for both networks | | [Stock Tokens](https://docs.robinhood.com/chain/stock-tokens/) | The chain's reference stock token conventions: one ERC-20 per asset, the `uiMultiplier` for corporate actions, per-asset price feeds and trading status checks | | [Robinhood Chain explorer](https://robinhoodchain.blockscout.com) | Blockscout explorer for mainnet transactions and contracts | Precursor share tokens follow the Robinhood Chain stock token conventions so that they behave predictably in wallets, oracles and DeFi integrations. See [Robinhood Chain](/architecture-and-security/robinhood-chain.md) for network details. ## Token standards | Standard | How Precursor uses it | | ------------------------------------------------------------------------------- | --------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | | [ERC-20](https://eips.ethereum.org/EIPS/eip-20) | Base interface for every Precursor Share Token | | [ERC-3643 (T-REX)](https://www.quicknode.com/guides/real-world-assets/erc-3643) | Permissioned token standard: identity registry, claim-based eligibility and modular transfer rules. See also the [T-REX whitepaper](https://tokeny.com/wp-content/uploads/2023/05/ERC3643-Whitepaper-T-REX-v4.pdf). | | ERC-8056 (Scaled UI Amount Extension) | The `uiMultiplier()` interface for splits and other corporate actions, as used by Robinhood Chain stock tokens. Described in the [Robinhood Chain Stock Tokens docs](https://docs.robinhood.com/chain/stock-tokens/). | | [EIP-712](https://eips.ethereum.org/EIPS/eip-712) | Typed structured data signing, used for RFQ quotes under the domain name `Precursor`, version `1` | | [ERC-1967 and UUPS (ERC-1822)](https://eips.ethereum.org/EIPS/eip-1822) | Proxy pattern for share tokens, with upgrades gated by `IssuerTimelock` | ## Oracles and pricing | Resource | What it covers | | ------------------------------------------------------------------------------------------------------------------ | ------------------------------------------------------------------------------------------------------------------------ | | [Chainlink: Robinhood Tokenized Equity Feeds](https://docs.chain.link/data-feeds/tokenized-equity-feeds/robinhood) | Per-asset price feeds on Robinhood Chain, how they incorporate the multiplier and how they behave when a token is paused | | [Chainlink Data Feeds API](https://docs.chain.link/data-feeds/api-reference) | The `AggregatorV3Interface`, which the `ValuationOracle` implements for compatible consumers | ## Network and infrastructure | Resource | What it covers | | ---------------------------------------------------------------------------------------------- | ------------------------------------------------------------------------------------------------------- | | [Arbitrum documentation](https://docs.arbitrum.io) | The rollup stack Robinhood Chain is built on, including sequencing and force inclusion through Ethereum | | [Blockscout documentation](https://docs.blockscout.com) | Explorer APIs used for contract verification and indexing | | [Alchemy: Robinhood Chain RPC](https://www.alchemy.com/rpc/robinhood) | Production RPC, WebSocket and archive access for mainnet | | [Alchemy: Robinhood Chain testnet RPC](https://www.alchemy.com/rpc/robinhood-testnet) | RPC access for testnet (chain ID `46630`) | | [Chainstack: Robinhood Chain](https://docs.chainstack.com/reference/robinhood-getting-started) | Alternative RPC provider used for failover | ## Libraries | Library | Use | | ----------------------------------------------------------------- | -------------------------------------------------------------------- | | [OpenZeppelin Contracts](https://docs.openzeppelin.com/contracts) | Base implementations for ERC-20, access control and proxies | | [Foundry](https://book.getfoundry.sh) | Contract development, testing and deployment | | [viem](https://viem.sh) | The on-chain helpers in `@precursor/sdk/onchain` are viem-compatible | --- # Agent Instructions This documentation is published with GitBook. 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