siwa

Name: siwa
Availability: InStock
Author: Bankr

Authenticate AI agents with ERC-8004 on-chain identity via signing and verification.

1.2k|589|Updated Jan 26, 2026

Search Tags:#authentication #middleware #web3 #nonce #erc-8004 #siwa #server-side-verification

Ready to run

npx skills add https://github.com/BankrBot/skills --skill siwa-bankrbot

💬 Prompt for ChatGPT / Claude Chat▼

Please help me install this Agent Skill.
Skill: siwa
Source: https://github.com/BankrBot/skills/tree/main/siwa
Command: npx skills add https://github.com/BankrBot/skills --skill siwa-bankrbot

SYSTEM DOCUMENTATION & REQUIREMENTS

💡 This Skill includes references (resource) components.

What problem does it solve?

SIWA enables AI agents to authenticate with services using their ERC-8004 onchain identity.

Core Features & Use Cases

Agent-side signing to prove ownership of an agent identity.
Server-side verification and nonce-based replay protection.
ERC-8128-based authenticated request middleware across Next.js, Express, Hono, and Fastify.
Modular SDK with signer, verifier, nonce-store and middlewares for multiple runtimes.

Quick Start

Install and integrate the SIWA SDK to begin signing and verifying agent identities in your app.

Frequently Asked Questions about siwa

High-intent search queries and answers about installing and using this skill.

FAQPage Schema

How do I authenticate AI agents using ERC-8004 on-chain identity?▼

To authenticate AI agents with ERC-8004 on-chain identity, use SIWA to handle agent-side message signing and server-side verification. It provides a modular SDK with nonce issuance and replay protection to securely validate agent identities.

What is the best way to add server-side verification for web3 agent authentication?▼

The best way to add server-side verification for web3 agent authentication is using middleware that validates ERC-8128-protected requests. SIWA offers verification modules across Next.js, Express, Hono, and Fastify runtimes to validate signed messages.

Does SIWA middleware work with Express and Next.js runtimes?▼

Yes, SIWA middleware works with Express and Next.js runtimes, alongside Hono and Fastify. The SDK provides modular middleware components to parse and verify ERC-8128-protected requests across these multiple server environments.

How do I prevent replay attacks when signing messages for AI agent authentication?▼

To prevent replay attacks during AI agent authentication, implement nonce-based replay protection. SIWA includes a nonce-store component that issues single-use nonces, ensuring each signed message and generated receipt is uniquely validated server-side.

Do I need an RPC URL and receipt secret to set up server-side web3 authentication?▼

Yes, you need to configure an RPC_URL and RECEIPT_SECRET in your environment to set up server-side web3 authentication. These variables are required by the @buildersgarden/siwa package to operate the signer and verifier workflows.

What are the limitations of using ERC-8004 identity for AI agent authentication?▼

A limitation of using ERC-8004 identity for AI agent authentication is the requirement for specific environment setup and the @buildersgarden/siwa package. The workflow depends on configuring an RPC_URL and RECEIPT_SECRET to process nonce issuance and receipt generation.