siwa-server-side

Verify SIWA signatures and issue ERC-8128 receipts for API routes.

43|12|Updated Feb 4, 2026
One-click install
npx skills add https://github.com/builders-garden/siwa --skill siwa-server-side
Or copy as Structured Prompt for Agent▼
Please help me install this Agent Skill.
Skill: siwa-server-side
Source: https://github.com/builders-garden/siwa/tree/main/packages/siwa-website/public/skills/server-side
Command: npx skills add https://github.com/builders-garden/siwa --skill siwa-server-side

SYSTEM DOCUMENTATION & REQUIREMENTS

Server-side SIWA verification enables secure API authentication by validating agents through nonce issuance, signed messages, and ERC-8128 receipts.

What problem does it solve?

This server-side flow prevents replay attacks and proves agent identity before granting access to protected endpoints.

Core Features & Use Cases

  • Nonce issuance: issue and manage nonces per agent for SIWA message signing.
  • Signature verification & receipts: verify messages and generate tamper-evident receipts for subsequent requests.
  • Framework integration: works with Next.js, Express, Hono, and Fastify to protect API routes.

Quick Start

Spin up the server-side SIWA flow to issue a nonce, verify a signed SIWA message, and obtain a verification receipt for API protection.

Frequently Asked Questions about siwa-server-side

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

FAQPage Schema
How do I prevent replay attacks during API authentication?▼

To prevent replay attacks during API authentication, you can issue per-agent nonces for SIWA message signing. This server-side flow validates signed messages and generates tamper-evident receipts before granting access to protected endpoints.

Does SIWA server-side verification work with Express and Next.js?▼

Yes, SIWA server-side verification works with Express, Next.js, Hono, and Fastify. The integration protects API routes by verifying agent signatures and issuing receipts within these supported frameworks.

What do I need to verify agent identities on the server?▼

To verify agent identities on the server, you need a Viem RPC client and a secure receipt secret. These components perform onchain checks and generate HMAC receipts for valid SIWA signatures.

How do I issue nonces for SIWA message signing?▼

You issue nonces for SIWA message signing through the server-side verification flow. This process issues and manages nonces per agent, ensuring each signed message is validated before generating an ERC-8128 receipt.

Why do I need a receipt secret for server-side SIWA verification?▼

You need a receipt secret to generate HMAC receipts during server-side SIWA verification. This creates tamper-evident receipts that prove agent identity and authorize subsequent requests to protected API endpoints.

What is the best way to protect API routes using SIWA signatures?▼

The best way to protect API routes using SIWA signatures is implementing a server-side flow with nonce issuance and ERC-8128 receipt generation. This validates agents and prevents unauthorized access across Next.js, Express, Hono, and Fastify.