# aspnetcore-authentication

> Claude/Codex skill by [@duendesoftware](https://omgskills.com/library/duendesoftware/index.md) · 9 stars · Updated 2026-10-16

ASP.NET Core authentication middleware configuration including OpenID Connect, JWT Bearer, cookie authentication, authentication schemes, challenge/forbid flows, and external identity provider integration.

Tags: ai-agents, claude, claude-code

## Install

```sh
git clone https://github.com/DuendeSoftware/duende-skills /tmp/duende-skills && ln -s /tmp/duende-skills/skills/aspnetcore-authentication ~/.claude/skills/aspnetcore-authentication
```

## From README

ASP.NET Core Authentication When to Use This Skill Use this skill when: Configuring OIDC authentication in an ASP.NET Core web application Setting up JWT Bearer authentication for an API Managing authentication schemes (cookies, OIDC, JWT, external providers) Implementing challenge, sign-in, sign-out, and forbid flows Debugging authentication failures (401s, redirect loops, claim mapping issues) Integrating with Duende IdentityServer as an OpenID Connect provider Configuring token validation parameters Core Principles Authentication ≠ Authorization — Authentication establishes who the user is. Authorization (see aspnetcore-authorization) determines what they can do. Scheme-Based Architecture — ASP.NET Core authentication is built around named schemes. Each scheme has a handler that knows how to authenticate, challenge, and sign out. Cookies for Web Apps, JWT for APIs — Web applications use cookie authentication (with OIDC for login). APIs use JWT Bearer or introspection.

## Links

- HTML page: https://omgskills.com/library/duendesoftware/duende-skills/skills/aspnetcore-authentication/
- GitHub: https://github.com/DuendeSoftware/duende-skills
- Author: [@duendesoftware](https://omgskills.com/library/duendesoftware/index.md)

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