update README and typo

README.md

@@ -1,3 +1,65 @@
 # ServiceStack.Jwks
 
-A JSON Web Key Set plugin for ServiceStack v5
+A ServiceStack v5 plugin to expose and consume [Json Web Key](https://tools.ietf.org/html/rfc7517) sets using a subset of the [OpenId discovery document](https://openid.net/specs/openid-connect-discovery-1_0.html).
+
+Potential use cases:
+-  simplify [JSON Web token](http://docs.servicestack.net/jwt-authprovider) key rotation between ServiceStack services
+-  protect a [stateless ServiceStack service](http://docs.servicestack.net/jwt-authprovider#services-only-validating-tokens) with a third-party authentication service that supports Open ID connect - Azure AD, Auth0, Okta, ...
+-  protect an ASP.NET Core app with the [Microsoft.AspNetCore.Authentication.JwtBearer](https://www.nuget.org/packages/Microsoft.AspNetCore.Authentication.JwtBearer/) middleware using the OpenID discovery document from a ServiceStack Authentication service.
+
+## Getting Started
+
+### Authentication service
+
+Register `JwksFeature` in the `AuthFeature`:
+
+```
+// existing Auth feature using the JwtAuthProvider
+var authFeature = new AuthFeature(...);
+
+authFeature.RegisterPlugins.Add(new JwksFeature());
+```
+
+The Discovery document is now accessible at `/openid-config` and the JSON Web key set at `/jwks`.
+
+### Protected ServiceStack service
+
+Register `JwksFeature` in the `AuthFeature`:
+
+```
+// existing Auth feature using the JwtAuthProviderReader
+var authFeature = new AuthFeature(...);
+
+authFeature.RegisterPlugins.Add(new JwksFeature() {
+    OpenIdDiscoveryUrl = "https://myauthapi.example.com/openid-config"
+    // or JwksUrl = "https://myauthapi.example.com/jwks"
+});
+```
+
+### Protected ASP.NET Core service
+
+```
+public class StartUp {
+    public void ConfigureServices(IServiceCollection services) {
+        ...
+        services.AddAuthentication(options => {
+            options.DefaultAuthenticateScheme = JwtBearerDefaults.AuthenticationScheme;
+            options.DefaultChallengeScheme = JwtBearerDefaults.AuthenticationScheme;
+        }).AddJwtBearer(options => {
+            // must match the configured audience on the ServiceStack Auth service
+            options.Audience = "my-audience"; 
+            // ServiceStack Auth service discovery url
+            options.MetadataAddress = "https://myauthapi.example.com/openid-config" 
+            // optional to map the Identity Name property to the `name` claim used by ServiceStack.
+            options.TokenValidationParameters.NameClaimType = "name"; 
+        });
+    }
+
+    public void Configure(IApplicationBuilder app) {
+        ...
+        // authenticate the user in the presence of a JWT Bearer token
+        app.UseAuthentication(); 
+        ...
+    }
+}
+```

src/JwksFeature.cs

@@ -45,7 +45,7 @@ protected virtual void LoadKeySet(JsonWebKeySetResponse keySet) {
             }
 
             if (JwtAuthProvider.RequireHashAlgorithm) {
-                // infer the algorithm is described by a key from the set
+                // infer the algorithm if it is described by a key from the set
                 var algo = keySet.Keys.FirstOrDefault(x => !string.IsNullOrEmpty(x.Algorithm))? .Algorithm;
                 if (algo != null) {
                     JwtAuthProvider.HashAlgorithm = algo;