YAMO Chain Server

This MCP Server acts as a bridge, allowing LLMs to interact with the YAMO Blockchain. It is now powered by @yamo/core for robust IPFS handling.

📦 Installation

# Global installation (recommended)
npm install -g @yamo/mcp-server

# Or use npx (no installation needed)
npx @yamo/mcp-server

🧰 Tools Provided

yamo_recall_lessons

Recalls past LessonLearned constraints stored by YAMO agents — Ghost Protection.

Call this at the start of each session to restore institutional memory and avoid repeating past mistakes. Returns raw YAMO block content strings; the calling LLM interprets and applies them as active constraints.

• Input: limit (optional, default: 5, max: 20)
• Output: Raw YAMO block strings joined with double newline
• Env: YAMO_MEMORY_PATH — path to LanceDB directory (default: ./data/memories.lance)

Architectural note: This server accesses memory in read-only mode. If a future requirement needs MCP sessions to store lessons, route writes through yamo-bridge via memory:shared — do not open the LanceDB store for direct writes from MCP.

yamo_submit_block

Submits a new reasoning block.

• Input: blockId, contentHash, etc.
• New Feature: content (string) and files (array). If provided, the server handles IPFS uploading and Deep Bundling automatically before signing.
• Encryption: Optional encryptionKey (string). If provided, the bundle is encrypted (AES-256-GCM) before upload, ensuring privacy for sensitive reasoning chains.

yamo_get_block

Retrieves full block data from the YAMO blockchain by its unique ID. Returns metadata including blockId, previousBlock, agentAddress, contentHash, timestamp, consensusType, ledger, and ipfsCID.

yamo_get_latest_block

Retrieves the most recently submitted YAMO block from the blockchain. Useful for automatically getting the chain tip to use as previousBlock for the next submission.

yamo_audit_block

Performs a cryptographic integrity audit of a block.

1. Fetches block metadata from blockchain.
2. Downloads content from IPFS.
3. Re-hashes the content locally.
4. Asserts LocalHash === ChainHash. Requires encryptionKey if the bundle is encrypted.

yamo_verify_block

Quickly verifies if a specific hash matches the immutable on-chain record for a block ID.

yamo_anchor_event

Anchors a YAMO provenance event on-chain (Phase 3). Submits a blockId and contentHash pair to the registry without IPFS content.

yamo_bridge_*

Tools for interacting with the YAMO bridge cluster (requires YAMO_BRIDGE_URL):

• yamo_bridge_list_kernels: Lists connected kernels and their skills.
• yamo_bridge_cluster_status: Shows bridge cluster status (Raft leader, members).
• yamo_bridge_invoke_skill: Invokes a skill on a capable kernel.

⚙️ Configuration

Option 1: Claude Desktop Integration (Recommended)

Add to your Claude Desktop config (claude_desktop_config.json):

With Global Installation:

{
  "mcpServers": {
    "yamo-chain": {
      "command": "yamo-mcp-server",
      "env": {
        "CONTRACT_ADDRESS": "0x3c9440fa8d604E732233ea17095e14be1a53b015",
        "RPC_URL": "https://ethereum-sepolia-rpc.publicnode.com",
        "PRIVATE_KEY": "0xYOUR_PRIVATE_KEY",
        "USE_REAL_IPFS": "false",
        "PINATA_JWT": "optional_if_using_real_ipfs"
      }
    }
  }
}

With npx (no installation):

{
  "mcpServers": {
    "yamo-chain": {
      "command": "npx",
      "args": ["@yamo/mcp-server"],
      "env": {
        "CONTRACT_ADDRESS": "0x3c9440fa8d604E732233ea17095e14be1a53b015",
        "RPC_URL": "https://ethereum-sepolia-rpc.publicnode.com",
        "PRIVATE_KEY": "0xYOUR_PRIVATE_KEY",
        "USE_REAL_IPFS": "false"
      }
    }
  }
}

Option 2: Standalone Usage

Set environment variables and run:

export CONTRACT_ADDRESS=0x3c9440fa8d604E732233ea17095e14be1a53b015
export RPC_URL=https://ethereum-sepolia-rpc.publicnode.com
export PRIVATE_KEY=0xYOUR_PRIVATE_KEY

# With global install
yamo-mcp-server

# Or with npx
npx @yamo/mcp-server

🌐 Networks

Sepolia Testnet (Production - Recommended)

Configuration:

• Contract: 0x3c9440fa8d604E732233ea17095e14be1a53b015
• RPC: https://ethereum-sepolia-rpc.publicnode.com

Requirements:

• ✅ Wallet with Sepolia ETH for gas
• ✅ Public RPC endpoint (no API key needed)

Local Development

Configuration:

• Contract: Deploy using @yamo/contracts
• RPC: http://127.0.0.1:8545

Requirements:

• ⚠️ Local Hardhat node must be running: npx hardhat node
• ⚠️ Contract must be deployed locally
• ⚠️ Wallet must be funded with local ETH

💰 Wallet Setup

1. Generate a Wallet

If you don't have a private key:

node -e "const ethers = require('ethers'); const w = ethers.Wallet.createRandom(); console.log('Address:', w.address); console.log('Private Key:', w.privateKey);"

2. Get Sepolia ETH (Testnet Only)

Your wallet needs Sepolia ETH for gas. Use your wallet address (not private key) with these faucets:

Alchemy Faucet (Fastest - 0.5 ETH):

• https://www.alchemy.com/faucets/ethereum-sepolia
• Sign in with Google/GitHub

PoW Faucet (No login - 0.05-0.1 ETH):

• https://sepolia-faucet.pk910.de/
• Mine for ~5 minutes

Google Cloud Faucet (0.05 ETH):

• https://cloud.google.com/application/web3/faucet/ethereum/sepolia

3. Check Your Balance

# Replace with your wallet address
curl -X POST https://ethereum-sepolia-rpc.publicnode.com \
  -H "Content-Type: application/json" \
  -d '{"jsonrpc":"2.0","method":"eth_getBalance","params":["0xYOUR_ADDRESS","latest"],"id":1}'

If result is "0x0", you need more ETH!

⚠️ Common Issues

"Sender doesn't have enough funds"

Problem: Your wallet has 0 ETH or insufficient balance

Solution:

1. Check you're using Sepolia RPC, not localhost
2. Verify your wallet address has Sepolia ETH (see faucets above)
3. Make sure PRIVATE_KEY matches the funded wallet

"Connection refused" or "ECONNREFUSED"

Problem: RPC_URL points to http://127.0.0.1:8545 but no local node running

Solution:

• For Sepolia: Change RPC to https://ethereum-sepolia-rpc.publicnode.com
• For Local: Start Hardhat node: cd packages/contracts && npx hardhat node

Balance shows 0 but I have ETH

Problem: Wrong network - you might have mainnet ETH, not Sepolia ETH

Solution:

1. Verify RPC is Sepolia: https://ethereum-sepolia-rpc.publicnode.com
2. Check balance on Sepolia: https://sepolia.etherscan.io/
3. Get Sepolia testnet ETH from faucets (see above)