Chaintool is an on-chain and dynamic toolchain built for CDP AgentKit that enables AI agents to discover and interact with smart contract tools dynamically. The system consists of a smart contract registry where anyone can register new tools, making them immediately available to all agents. Each tool is documented with descriptions and ABIs, allowing AI agents to understand and utilize them without prior knowledge.

The key innovation is that agents can discover and use new tools while they are running, even if they didn't have access to them during initialization. Furthermore, agentic tools are now realized as on-chain assets, exposing them to the many applications of dApps. This creates an expandable ecosystem of agent-compatible smart contract tools that can grow organically.

The project is built using several modern web3 technologies and devtools.

Smart Contracts

• Solidity (solc 0.8.28)
• Foundry for development and testing
• Deployed on Base Sepolia network

Agent SDK

• Built with Bun runtime
• Integrates with CDP (Coinbase Developer Platform)
• Uses OpenAI for the AI component
• Implements HDKey wallets with Viem for blockchain interactions, derived from CDP Wallet seed
• AgentKit integration for agent behaviors, 4 actions for Chaintool
• Nillion SecretVault to save & restore used Chaintool history via 2 actions

Frontend

• Web interface deployed on Vercel
• Uses OnchainKit for blockchain interactions
• Used React & Vite for development

Architecture

• Core registry contract (AgentToolRegistry) that manages tool registration
• Tools are defined as structs containing metadata (name, description, ABI types, categories) where ABIs are human-readable ABI types for better AI comprehension
• Implements EVM-compatible smart contracts for multi-chain capabilities