Strawberry.fun Agent Kit Core

The Agent Kit Core provides a foundation for building AI agents that can interact with Strawberry.fun Tool Servers and execute various actions.

This library provides framework-agnostic primitives that are meant to be composable and used via the Agent Kit's framework-specific extensions (e.g. LangChain).

Installation

npm install @strawberryprotocol/str-agentkit-core

Basic Usage

import { StrawberryAgentkit } from '@strawberryprotocol/str-agentkit-core';

// Configure the agent kit
const agentkit = await StrawberryAgentkit.configure({
  sourceVersion: '1.0.0',
  chain: baseSepolia,
  // Optional: Specify tools to use
  tools: ['contract_address/tool_name'],
  // Optional: Configure MCP servers
  mcpServers: [{ uri: 'http://localhost:3000/sse' }]
});

// Get available actions
const actions = agentkit.getActions();

// Execute an action
const result = await agentkit.run(action, args);

// Clean up
await agentkit.close();

Tool Discovery

The Agent Kit uses an on-chain discovery mechanism to find and load tools. Each Strawberry token contract contains an apiURI that points to its MCP server. When you configure the Agent Kit with tool specifications, it:

1. Reads the contract addresses from your tool specifications
2. Queries each contract's apiURI to discover its MCP server
3. Connects to each server and loads available tools

Client Types

The Agent Kit supports two types of clients for interacting with the blockchain:

1. Public Client: Used for reading data from the blockchain (e.g., discovering tool servers). A default public client is created if none is provided, using the Base Sepolia RPC URL.

2. Wallet Client: Required for operations that need signing (e.g., using gated tools that require signatures). No default wallet client is provided - you must configure one if you want to use tools that require signatures.

Example configuration with both client types:

import { StrawberryAgentkit } from '@strawberryprotocol/str-agentkit-core';
import { createPublicClient, createWalletClient, http } from 'viem';
import { privateKeyToAccount } from 'viem/accounts';
import { baseSepolia } from 'viem/chains';

// Create public client for reading from chain
const publicClient = createPublicClient({
  chain: baseSepolia,
  transport: http("https://your-rpc-url"),
});

// Create wallet client for signing
const account = privateKeyToAccount("your-private-key");
const walletClient = createWalletClient({
  account,
  chain: baseSepolia,
  transport: http(),
});

// Configure agentkit with both clients
const agentkit = await StrawberryAgentkit.configure({
  chain: baseSepolia,
  publicClient,  // Optional - defaults to Base Sepolia RPC
  walletClient,  // Required for tools that need signing
  tools: ["0x1234.../gated-tool"],
});

Tool Specification Format

Tools can be specified in two formats:

// 1. Full contract address with specific tool
"0x1234.../echo"  // Only load the "echo" tool from this contract

// 2. Full contract address with wildcard
"0x1234.../*"     // Load all tools from this contract

Examples

import { StrawberryAgentkit } from '@strawberryprotocol/str-agentkit-core';
import { baseSepolia } from 'viem/chains';
import { createPublicClient, createWalletClient, http } from 'viem';
import { privateKeyToAccount } from 'viem/accounts';

// Example 1: Basic configuration with default public client
const agentkit1 = await StrawberryAgentkit.configure({
  chain: baseSepolia,
  tools: [
    "0x439cd160C7bb70D1D69F9F71Ef550e287234614B/*"  // Load all tools
  ]
});

// Example 2: Configuration with custom public client
const publicClient = createPublicClient({
  chain: baseSepolia,
  transport: http("https://your-rpc-url"),
});

const agentkit2 = await StrawberryAgentkit.configure({
  chain: baseSepolia,
  publicClient,
  tools: [
    "0x439cd160C7bb70D1D69F9F71Ef550e287234614B/echo",  // Only load echo tool
    "0x905Ad472d7eeB94ed1Fc29D8ff4B53FD4D5a5Eb4/weatherByLatLng"  // Only allow weather by latlng tool
  ]
});

// Example 3: Configuration with wallet for signing
const account = privateKeyToAccount("0x...");
const walletClient = createWalletClient({
  account,
  chain: baseSepolia,
  transport: http(),
});

const agentkit3 = await StrawberryAgentkit.configure({
  chain: baseSepolia,
  walletClient,
  tools: [
    "0x439cd160C7bb70D1D69F9F71Ef550e287234614B/gated-echo",  // Load gated echo tool that requires signing
  ]
});

How It Works

1. Contract Discovery: When you initialize the Agent Kit, it looks at each contract address in your tool specifications.

2. API URI Resolution: For each contract, it calls the apiURI() function to get the MCP server URL:

   // On the contract
   function apiURI() public view returns (string memory)

3. Server Connection: The Agent Kit connects to each discovered MCP server using the Model Context Protocol.

4. Tool Loading: It then loads the available tools from each server, filtering them based on your tool specifications:

   • If you specified a specific tool (e.g., "contract/echo"), only that tool is loaded
   • If you used a wildcard (e.g., "contract/*"), all tools from that contract are loaded

5. Tool Availability: The loaded tools become available through the getActions() method and can be executed using run().

This discovery mechanism allows for dynamic tool loading based on on-chain registries, making tools automatically discoverable as long as they're properly registered in a Strawberry token contract.

Argument Signing

The Agent Kit supports EIP-712 typed data signing for tool arguments. This allows tools to verify the authenticity and integrity of arguments passed to them.

EIP-712 Domain

Each tool uses the following EIP-712 domain for signing:

const domain = {
  name: "Strawberry.fun",
  version: "1",
  chainId: 84532, // Base Sepolia
  verifyingContract: "0x..." // Optional: Contract address of the tool
};

Argument Type Conversion

Tool arguments are automatically converted from JSON Schema types to EIP-712 types:

| JSON Schema Type | EIP-712 Type | |-----------------|--------------| | string | string | | number/integer | uint256 | | boolean | bool |

Example:

// Tool argument schema
const schema = {
  type: "object",
  properties: {
    message: { type: "string" },
    amount: { type: "number" },
    isActive: { type: "boolean" }
  }
};

// Generated EIP-712 types
const types = {
  ToolArgs: [
    { name: "message", type: "string" },
    { name: "amount", type: "uint256" },
    { name: "isActive", type: "bool" }
  ]
};

Signing Arguments

You can sign tool arguments using the provided utilities:

import { StrawberryAgentkit } from '@strawberryprotocol/str-agentkit-core';
import { createWalletClient } from 'viem';

// Create a wallet client
const wallet = createWalletClient({
  account,
  chain: baseSepolia,
  transport: http()
});

// Configure the agent kit
const agentkit = await StrawberryAgentkit.configure({
  chain: baseSepolia,
  tools: ["0x.../tool"]
});

// Get an action
const action = agentkit.getActions()[0];

// Sign and execute with arguments
const args = {
  message: "Hello World",
  amount: 123,
  isActive: true
};

const result = await agentkit.run(action, args, {
  signer: wallet // Optional: If provided, arguments will be signed
});

Verifying Signatures

Tools can verify the signatures of received arguments:

import { verifyToolArgumentSignature } from '@strawberryprotocol/str-agentkit-core';

// In your tool implementation
const isValid = await verifyToolArgumentSignature(
  domain,
  schema,
  args,
  signature,
  signerAddress
);

This signing mechanism ensures:

1. Argument integrity (arguments haven't been tampered with)
2. Authenticity (arguments were signed by a known address)
3. Type safety (arguments match the expected schema)

Key Components

StrawberryAgentkit Class

The main class that manages connections to MCP servers and handles action execution. It provides:

• MCP server discovery and connection management
• Action registration and execution
• Tool management and filtering
• Argument signing and verification

Development

npm install
npx jest 

License

MIT License