diff --git a/Errors.cs b/Errors.cs
new file mode 100644
index 0000000..50d27d1
--- /dev/null
+++ b/Errors.cs
@@ -0,0 +1,17 @@
+namespace matrix_dotnet;
+
+public class LoginRequiredException : UnauthorizedAccessException { }
+
+public class MatrixApiError : Exception {
+	public string ErrorCode { get; }
+	public string ErrorMessage { get; }
+	public HttpResponseMessage Response { get; }
+
+	public MatrixApiError(string errorCode, string errorMessage, HttpResponseMessage response, Exception? innerException)
+		: base(String.Format("Request to Matrix API failed: {0}: {1}", errorCode, errorMessage), innerException) {
+		ErrorCode = errorCode;
+		ErrorMessage = errorMessage;
+		Response = response;
+	}
+}
+
diff --git a/MatrixApi.cs b/MatrixApi.cs
index 32dd060..7ce4199 100644
--- a/MatrixApi.cs
+++ b/MatrixApi.cs
@@ -2,13 +2,18 @@ namespace matrix_dotnet;
 
 using Refit;
 
+/// <summary>
+/// The IMatrixApi interface represents API endpoints directly and its implementation gets generated by Refit.
+/// </summary>
 public interface IMatrixApi {
+	public record ErrorResponse(string errcode, string error, bool? soft_logout = null);
 
 	public abstract record Identifier(string Type, string? User = null, string? Country = null, string? Phone = null, string? Medium = null, string? Address = null);
 	public record UserIdentifier(string user) : Identifier("m.id.user", User: user);
 	public record PhoneIdentifier(string country, string phone) : Identifier("m.id.phone", Country: country, Phone: phone);
 	public record ThirdpartyIdentifier(string medium, string address) : Identifier("m.id.thirdparty", Medium: medium, Address: address);
 
+	/// <summary>The return value of the <see cref="Login"/> function.</summary>
 	public record LoginResponse(
 		string access_token,
 		string device_id,
@@ -19,6 +24,7 @@ public record LoginResponse(
 		string user_id
 	);
 
+	/// <summary><see cref="Login"/></summary>
 	public abstract record LoginRequest(
 		string type,
 		Identifier identifier,
@@ -29,6 +35,7 @@ public abstract record LoginRequest(
 		bool refresh_token = true
 	);
 
+	/// <summary><see cref="Login"/></summary>
 	public record PasswordLoginRequest(
 			Identifier identifier,
 			string password,
@@ -37,6 +44,7 @@ public record PasswordLoginRequest(
 			bool refresh_token = true
 	) : LoginRequest("m.login.password", identifier, password, null, initial_device_display_name, device_id, refresh_token);
 
+	/// <summary><see cref="Login"/></summary>
 	public record TokenLoginRequest(
 			Identifier identifier,
 			string token,
@@ -67,3 +75,4 @@ public record SendEventResponse(string event_id);
 	[Headers("Authorization: Bearer")]
 	public Task<SendEventResponse> SendEvent<T>(string roomId, string eventType, string txnId, T body);
 }
+
diff --git a/MatrixClient.cs b/MatrixClient.cs
index 5e0f3ae..a4a9907 100644
--- a/MatrixClient.cs
+++ b/MatrixClient.cs
@@ -26,51 +26,23 @@ public bool Expired {
 		get => AccessToken is not null && ExpiresAt is not null && ExpiresAt < DateTime.Now;
 	}
 
-	public class LoginRequiredException : UnauthorizedAccessException { }
-
 	private async Task<string> GetAccessToken(HttpRequestMessage request, CancellationToken ct) {
 		if (!LoggedIn) throw new LoginRequiredException();
 		if (Expired) await Refresh();
 		return AccessToken!;
 	}
 
-	public record ErrorResponse(string errcode, string error, bool? soft_logout = null);
-
-	public class ApiError : Exception {
-		public string ErrorCode { get; }
-		public string ErrorMessage { get; }
-		public HttpResponseMessage Response { get; }
-
-		public ApiError(string errorCode, string errorMessage, HttpResponseMessage response, Exception? innerException)
-			: base(String.Format("Request to Matrix API failed: {0}: {1}", errorCode, errorMessage), innerException) {
-			ErrorCode = errorCode;
-			ErrorMessage = errorMessage;
-			Response = response;
-		}
-	}
-
 	private RefitSettings RefitSettings;
 
-	private class RetryException : Exception { }
-
-	private static async Task<TResult> RetryAsync<TResult>(Func<Task<TResult>> func) {
-	retry:
-		try {
-			return await func();
-		} catch (RetryException) {
-			goto retry;
-		}
-	}
-
 	private async Task<Exception?> ExceptionFactory(HttpResponseMessage response) {
 		if (response.IsSuccessStatusCode) return null;
 
-		var errorResponse = JsonSerializer.Deserialize<ErrorResponse>(await response.Content.ReadAsStringAsync());
+		var errorResponse = JsonSerializer.Deserialize<IMatrixApi.ErrorResponse>(await response.Content.ReadAsStringAsync());
 		if (errorResponse is not null) {
 			if (errorResponse.errcode == "M_UNKNOWN_TOKEN") {
 				if (errorResponse.soft_logout is not null && errorResponse.soft_logout!.Value) {
 					await Refresh();
-					return new RetryException();
+					return new Retry.RetryException();
 				} else {
 					AccessToken = null;
 					RefreshToken = null;
@@ -79,7 +51,7 @@ private static async Task<TResult> RetryAsync<TResult>(Func<Task<TResult>> func)
 				}
 			}
 
-			return new ApiError(errorResponse.errcode, errorResponse.error, response, null);
+			return new MatrixApiError(errorResponse.errcode, errorResponse.error, response, null);
 		}
 
 		return await ApiException.Create(
@@ -119,6 +91,11 @@ public MatrixClient(Uri homeserver, ILogger? logger = null) {
 		Api = RestService.For<IMatrixApi>(apiUrlB.Uri.ToString(), RefitSettings);
 	}
 
+	private void UpdateExpiresAt(int? expiresInMs) {
+		if (expiresInMs is null) ExpiresAt = null;
+		else ExpiresAt = DateTime.Now.AddMilliseconds((double)expiresInMs);
+	}
+
 	private async Task Login(IMatrixApi.LoginRequest request) {
 		var response = await Api.Login(request);
 
@@ -129,11 +106,6 @@ private async Task Login(IMatrixApi.LoginRequest request) {
 		UpdateExpiresAt(response.expires_in_ms);
 	}
 
-	private void UpdateExpiresAt(int? expiresInMs) {
-		if (expiresInMs is null) ExpiresAt = null;
-		else ExpiresAt = DateTime.Now.AddMilliseconds((double)expiresInMs);
-	}
-
 	public async Task PasswordLogin(string username, string password, string? initialDeviceDisplayName = null, string? deviceId = null)
 		=> await PasswordLogin(new IMatrixApi.UserIdentifier(username), password, initialDeviceDisplayName, deviceId);
 
@@ -157,8 +129,9 @@ public async Task Refresh() {
 		UpdateExpiresAt(response.expires_in_ms);
 	}
 
+
 	public async Task<string[]> GetJoinedRooms() {
-		var response = await RetryAsync(async () => await Api.GetJoinedRooms());
+		var response = await Retry.RetryAsync(async () => await Api.GetJoinedRooms());
 
 		return response.joined_rooms;
 	}
@@ -167,7 +140,7 @@ public abstract record Message(string body, string msgtype);
 	public record TextMessage(string body) : Message(body: body, msgtype: "m.text");
 
 	public async Task<string> SendMessage<TMessage>(string roomId, TMessage message) where TMessage : Message {
-		var response = await RetryAsync(async () => await Api.SendEvent(roomId, "m.room.message", GenerateTransactionId(), message));
+		var response = await Retry.RetryAsync(async () => await Api.SendEvent(roomId, "m.room.message", GenerateTransactionId(), message));
 
 		return response.event_id;
 	}
diff --git a/Util.cs b/Util.cs
new file mode 100644
index 0000000..bf26fdf
--- /dev/null
+++ b/Util.cs
@@ -0,0 +1,15 @@
+namespace matrix_dotnet;
+
+class Retry {
+	public class RetryException : Exception {}
+
+	public static async Task<TResult> RetryAsync<TResult>(Func<Task<TResult>> func) {
+	retry:
+		try {
+			return await func();
+		} catch (RetryException) {
+			goto retry;
+		}
+	}
+}
+