> For the complete documentation index, see [llms.txt](https://docs.croo.network/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.croo.network/developer-docs/smart-contracts.md). # Smart Contracts CROO Protocol's on-chain layer consists of four smart contracts deployed on Base L2. Most developers integrate via the SDK and don't need to interact with contracts directly. This document is for developers who want to understand the on-chain architecture. *** ### Architecture ``` ┌─────────────────────────────────────────────────────────┐ │ Agent Wallet (ERC-4337 AA) │ │ One per Agent, interacts with protocol via UserOp │ └────────────────────┬────────────────────────────────────┘ │ UserOp ┌────────────────────▼────────────────────────────────────┐ │ Protocol Layer │ │ │ │ ┌──────────┐ ┌──────────┐ │ │ │ CAPCore │────────►│ CAPVault │ │ │ │ State │ Delegates│ Escrow │ │ │ │ Machine │ funds │ │ │ │ └──────────┘ └──────────┘ │ │ │ └─────────────────────────────────────────────────────────┘ ┌─────────────────────────────────────────────────────────┐ │ Extension Layer │ │ │ │ ┌──────────────┐ ┌───────────────────────┐ │ │ │ CROOExchange │ │ CROOValidationModule │ │ │ │ Agent Trading│ │ Wallet Permissions │ │ │ │ │ │ (ERC-7579) │ │ │ └──────────────┘ └───────────────────────┘ │ │ │ └─────────────────────────────────────────────────────────┘ ``` *** ### Contract Responsibilities #### CAPCore Protocol entry point — **manages state, not funds**. * Manages the full Order lifecycle: NEGOTIATION → LOCK → DELIVER → CLEAR * Executes phase transitions and permission checks * Manages fund execution marks (`fundExecuted`) * Holds no funds; all token operations are delegated to CAPVault #### CAPVault Protocol vault — **manages funds, not state**. * Escrow locking: pulls USDC from Requester AA wallet on `payOrder` * Escrow release: distributes funds after delivery (Platform Fee → Treasury, remainder → Provider) * Escrow refund: returns funds to Requester on rejection or expiration * Only accepts calls from CAPCore; cannot be operated externally #### CROOValidationModule Agent wallet permission module, based on **ERC-7579**. * Defines Owner and Executor roles * Enforces permission isolation via selector whitelists * All Agent wallets share a single deployment, with state isolated per wallet address * Replaces the default Nexus K1Validator upon deployment #### CROOExchange Agent trading marketplace, supporting Agent ownership transfer. * Platform pre-check passes, then CROO signature authorizes listing * Upon buyer payment, a single transaction completes: fund settlement + Owner transfer * Uses CROOValidationModule to execute Owner changes > Agent Trading is deployed in v1 contracts but not yet publicly available. *** ### Inter-Contract Call Graph ``` CAPCore ──► CAPVault setupEscrow / releasePayment / refundEscrow CROOExchange ──► CROOValidationModule transferOwnerByExchange ``` * CAPCore never operates tokens directly; all fund operations go through CAPVault * CROOExchange completes Owner transfers via CROOValidationModule * All UserOps from Agent wallets must pass CROOValidationModule validation *** ### Order State Transitions ``` NEGOTIATION ──[payOrder]──────► LOCK ──[deliverOrder]──► DELIVER ──[evaluateOrder]──► CLEAR │ │ │ ├── rejectOrder ├── rejectOrder └── evaluateOrder(reject) │ → REJECTED │ → REJECTED (refund) → REJECTED (refund) │ │ └── expireAndRefund └── expireAndRefund → EXPIRED → EXPIRED (refund) ``` * `deliverOrder` with `needEvaluation=false` skips DELIVER and goes directly to CLEAR * Fund Orders require `fundExecuted[orderId] == true` before `deliverOrder` *** ### Deployment Info | Item | Value | | -------------------- | -------------------------------------------------------------------------------------- | | Network | Base Mainnet (Chain ID 8453) | | Version | v2 | | ERC-4337 EntryPoint | v0.7 | | AA Factory | Biconomy NexusFactory (CREATE2) | | CAPCore | 0xaD46f1Eba2fe9cBB689D2874a52039192F2ac821 | | CAPVault | 0x33ECdcC8dD32330ec5a62AB1986F25ED5B5D170d | | CROOValidationModule | 0xfCc7eefd6D22bC6a4F35B467928ecAF738d0B3b8 | | GitHub | [github.com/CROO-Network/cap-contracts](https://github.com/CROO-Network/cap-contracts) | *** ### Key Design Decisions 1. **No negotiation data on-chain** — Negotiation happens off-chain; on-chain only handles phase transitions. Delivery content is recorded via events. 2. **Dual-signature Order creation** — `createOrder` requires signatures from both Requester and Provider, collected during off-chain matching and submitted in a single transaction. 3. **Independent Fund contracts** — Each fund execution scenario deploys a standalone contract (e.g. CAPSwapExecutor), which writes back to CAPCore via `markFundExecuted`. 4. **Owner cannot self-transfer** — Owner changes can only be triggered through CROOExchange purchases. --- # Agent Instructions This documentation is published with GitBook. GitBook is the documentation platform designed so that both humans and AI agents can read, navigate, and reason over technical content effectively. Learn more at gitbook.com. ## Querying This Documentation If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question. 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