How do I install Foundry Zksync?

Copy the stdio config for Cursor, Claude Desktop, Claude Code, or VS Code on this page. It uses the publisher's install, not a PlugMCP proxy.

Does Foundry Zksync need an API key?

No required environment variable is listed on this record.

What transport does Foundry Zksync use?

Foundry Zksync runs locally over stdio.

When was Foundry Zksync last checked?

Last checked 2026-10-20. Expose foundry-zksync (forge, cast, anvil-zksync) tools for zkSync Era development

Foundry Zksync MCP server

foundry-zksync-mcp

An MCP (Model Context Protocol) server that exposes foundry-zksync CLI tools to AI assistants like Claude.

Tools

Tool	Description
`init`	`forge init` with automatic zkSync config
`compile`	`forge build --zksync`
`test`	`forge test --zksync` with filter/verbosity options
`run_script`	`forge script --zksync` with broadcast, sender, slow mode
`deploy`	`forge create --zksync` with structured output parsing
`verify`	`forge verify-contract --zksync` (Etherscan & zkSync Explorer)
`install`	`forge install` for dependency management
`clean`	`forge clean` to remove build artifacts
`gas_report`	`forge test --gas-report` for gas usage analysis
`snapshot`	`forge snapshot` for gas benchmarking
`read_foundry_toml`	Read and inspect project configuration
`explain`	Match errors/logs against a knowledge base of zkSync gotchas
`cast_abi_encode`	`cast abi-encode`
`cast_abi_decode`	`cast abi-decode`
`cast_calldata_decode`	`cast calldata-decode`
`cast_call`	`cast call` for read-only contract interaction
`cast_send`	`cast send` for state-changing transactions
`cast_balance`	`cast balance` for ETH balance queries
`cast_nonce`	`cast nonce` for transaction nonce queries
`get_zksync_docs`	Look up foundry-zksync documentation by topic
`anvil_zksync`	Start or check a local anvil-zksync dev node

Prerequisites

Node.js >= 18
foundry-zksync installed (foundryup-zksync)

Quick Start (npx)

No install needed — run directly with npx:

claude mcp add foundry-zksync -- npx -y foundry-zksync-mcp

Or add to claude_desktop_config.json / ~/.claude.json:

{
  "mcpServers": {
    "foundry-zksync": {
      "command": "npx",
      "args": ["-y", "foundry-zksync-mcp"]
    }
  }
}

Install from Source

git clone https://github.com/Jrigada/foundry-zksync-mcp.git
cd foundry-zksync-mcp
npm install
npm run build

Then register with Claude Code:

claude mcp add foundry-zksync node /absolute/path/to/foundry-zksync-mcp/dist/index.js

Key Management

All signing tools (deploy, cast_send, run_script) support multiple wallet methods. Choose based on your security needs:

Local Development (anvil-zksync)

For local dev with well-known test keys, use privateKey directly:

privateKey: "0xac0974bec39a17e36ba4a6b4d238ff944bacb478cbed5efcae784d7bf4f2ff80"

These are the default anvil-zksync test accounts — they hold no real value.

Warning: Never use privateKey with keys that hold real funds. MCP tool parameters are visible to the AI assistant and may be logged.

Recommended for Production: Named Keystores

Keys are encrypted on disk — only the account name travels through MCP.

# Import a private key into a named keystore (interactive, key never shown)
cast wallet import deployer --interactive

# List your keystores
ls ~/.foundry/keystores/

Then use account: "deployer" in any signing tool. Forge will prompt for the password at runtime, or you can point to a password file with passwordFile.

Keystore Files

If you have an existing encrypted keystore JSON file (e.g. from Geth, MetaMask export):

keystore: "/path/to/keystore.json"
passwordFile: "/path/to/password.txt"

Hardware Wallets

ledger: true    # Ledger
trezor: true    # Trezor

Cloud KMS

aws: true       # AWS KMS (set AWS_KMS_KEY_ID env var)
gcp: true       # Google Cloud KMS (set GCP_PROJECT_ID, GCP_LOCATION, etc.)

Signing Method Summary

Method	Key Exposure	Best For
Hardware wallet	None (key never leaves device)	High-value production
Cloud KMS	None (key in HSM)	Automated production
Named keystore (`account`)	None through MCP (encrypted on disk)	General production use
Keystore file	None through MCP (encrypted on disk)	Existing workflows
`privateKey`	Visible to AI assistant	Local dev with test keys only

Project Structure

src/
  index.ts              MCP server entry point, registers all 21 tools
  knowledge.ts          Knowledge base (45+ entries) and system addresses
  tools/
    shared.ts           Profile field and env builder shared across forge tools
    init.ts             forge init with zkSync config
    compile.ts          forge build --zksync
    test.ts             forge test --zksync
    run_script.ts       forge script --zksync
    deploy.ts           forge create --zksync (structured output)
    verify.ts           forge verify-contract --zksync
    install.ts          forge install
    clean.ts            forge clean
    gas_report.ts       forge test --gas-report
    snapshot.ts         forge snapshot
    read_foundry_toml.ts  Read project config
    explain.ts          Error/log explanation with knowledge base
    get_zksync_docs.ts  Documentation lookup with embedded content
    cast_abi_encode.ts  cast abi-encode
    cast_abi_decode.ts  cast abi-decode
    cast_calldata_decode.ts  cast calldata-decode
    cast_call.ts        cast call
    cast_send.ts        cast send
    cast_balance.ts     cast balance
    cast_nonce.ts       cast nonce
    anvil_zksync.ts     anvil-zksync node management
  __tests__/            133 tests (vitest)

foundry-zksync-mcp

An MCP (Model Context Protocol) server that exposes foundry-zksync CLI tools to AI assistants like Claude.

Tools

Tool	Description
`init`	`forge init` with automatic zkSync config
`compile`	`forge build --zksync`
`test`	`forge test --zksync` with filter/verbosity options
`run_script`	`forge script --zksync` with broadcast, sender, slow mode
`deploy`	`forge create --zksync` with structured output parsing
`verify`	`forge verify-contract --zksync` (Etherscan & zkSync Explorer)
`install`	`forge install` for dependency management
`clean`	`forge clean` to remove build artifacts
`gas_report`	`forge test --gas-report` for gas usage analysis
`snapshot`	`forge snapshot` for gas benchmarking
`read_foundry_toml`	Read and inspect project configuration
`explain`	Match errors/logs against a knowledge base of zkSync gotchas
`cast_abi_encode`	`cast abi-encode`
`cast_abi_decode`	`cast abi-decode`
`cast_calldata_decode`	`cast calldata-decode`
`cast_call`	`cast call` for read-only contract interaction
`cast_send`	`cast send` for state-changing transactions
`cast_balance`	`cast balance` for ETH balance queries
`cast_nonce`	`cast nonce` for transaction nonce queries
`get_zksync_docs`	Look up foundry-zksync documentation by topic
`anvil_zksync`	Start or check a local anvil-zksync dev node

Prerequisites

Node.js >= 18
foundry-zksync installed (foundryup-zksync)

Quick Start (npx)

No install needed — run directly with npx:

claude mcp add foundry-zksync -- npx -y foundry-zksync-mcp

Or add to claude_desktop_config.json / ~/.claude.json:

{
  "mcpServers": {
    "foundry-zksync": {
      "command": "npx",
      "args": ["-y", "foundry-zksync-mcp"]
    }
  }
}

Install from Source

git clone https://github.com/Jrigada/foundry-zksync-mcp.git
cd foundry-zksync-mcp
npm install
npm run build

Then register with Claude Code:

claude mcp add foundry-zksync node /absolute/path/to/foundry-zksync-mcp/dist/index.js

Key Management

All signing tools (deploy, cast_send, run_script) support multiple wallet methods. Choose based on your security needs:

Local Development (anvil-zksync)

For local dev with well-known test keys, use privateKey directly:

privateKey: "0xac0974bec39a17e36ba4a6b4d238ff944bacb478cbed5efcae784d7bf4f2ff80"

These are the default anvil-zksync test accounts — they hold no real value.

Warning: Never use privateKey with keys that hold real funds. MCP tool parameters are visible to the AI assistant and may be logged.

Recommended for Production: Named Keystores

Keys are encrypted on disk — only the account name travels through MCP.

# Import a private key into a named keystore (interactive, key never shown)
cast wallet import deployer --interactive

# List your keystores
ls ~/.foundry/keystores/

Then use account: "deployer" in any signing tool. Forge will prompt for the password at runtime, or you can point to a password file with passwordFile.

Keystore Files

If you have an existing encrypted keystore JSON file (e.g. from Geth, MetaMask export):

keystore: "/path/to/keystore.json"
passwordFile: "/path/to/password.txt"

Hardware Wallets

ledger: true    # Ledger
trezor: true    # Trezor

Cloud KMS

aws: true       # AWS KMS (set AWS_KMS_KEY_ID env var)
gcp: true       # Google Cloud KMS (set GCP_PROJECT_ID, GCP_LOCATION, etc.)

Signing Method Summary

Method	Key Exposure	Best For
Hardware wallet	None (key never leaves device)	High-value production
Cloud KMS	None (key in HSM)	Automated production
Named keystore (`account`)	None through MCP (encrypted on disk)	General production use
Keystore file	None through MCP (encrypted on disk)	Existing workflows
`privateKey`	Visible to AI assistant	Local dev with test keys only

Project Structure

src/
  index.ts              MCP server entry point, registers all 21 tools
  knowledge.ts          Knowledge base (45+ entries) and system addresses
  tools/
    shared.ts           Profile field and env builder shared across forge tools
    init.ts             forge init with zkSync config
    compile.ts          forge build --zksync
    test.ts             forge test --zksync
    run_script.ts       forge script --zksync
    deploy.ts           forge create --zksync (structured output)
    verify.ts           forge verify-contract --zksync
    install.ts          forge install
    clean.ts            forge clean
    gas_report.ts       forge test --gas-report
    snapshot.ts         forge snapshot
    read_foundry_toml.ts  Read project config
    explain.ts          Error/log explanation with knowledge base
    get_zksync_docs.ts  Documentation lookup with embedded content
    cast_abi_encode.ts  cast abi-encode
    cast_abi_decode.ts  cast abi-decode
    cast_calldata_decode.ts  cast calldata-decode
    cast_call.ts        cast call
    cast_send.ts        cast send
    cast_balance.ts     cast balance
    cast_nonce.ts       cast nonce
    anvil_zksync.ts     anvil-zksync node management
  __tests__/            133 tests (vitest)

Foundry Zksync

Add this server

Host a copy with our keys and logs.

Related MCP

Related skills

Questions

foundry-zksync-mcp

Tools

Prerequisites

Quick Start (npx)

Install from Source

Key Management

Local Development (anvil-zksync)

Recommended for Production: Named Keystores

Keystore Files

Hardware Wallets

Cloud KMS

Signing Method Summary

Project Structure

Foundry Zksync

Add this server

Host a copy with our keys and logs.

Related MCP

Related skills

Questions

foundry-zksync-mcp

Tools

Prerequisites

Quick Start (npx)

Install from Source

Key Management

Local Development (anvil-zksync)

Recommended for Production: Named Keystores

Keystore Files

Hardware Wallets

Cloud KMS

Signing Method Summary

Project Structure