diff --git a/docs/todo.md b/docs/todo.md
index 9703d02..634bf8e 100644
--- a/docs/todo.md
+++ b/docs/todo.md
@@ -23,13 +23,13 @@
             - [ ] 5.3.4.7   Dummy Auth
         - [ ] 5.3.5   Fallback
             - [ ] 5.3.5.1   Example
-        - [ ] 5.3.6   Identifier types
-            - [ ] 5.3.6.1   Matrix User ID
-            - [ ] 5.3.6.2   Third-party ID
-            - [ ] 5.3.6.3   Phone number
+        - [x] ~~5.3.6   Identifier types~~
+            - [x] ~~5.3.6.1   Matrix User ID~~
+            - [x] ~~5.3.6.2   Third-party ID~~
+            - [x] ~~5.3.6.3   Phone number~~
     - [ ] 5.4   Login
         - [x] 5.4.1   ~~GET /_matrix/client/r0/login~~
-        - [ ] 5.4.2   POST /_matrix/client/r0/login
+        - [x] 5.4.2   ~~POST /_matrix/client/r0/login~~
         - [ ] 5.4.3   POST /_matrix/client/r0/logout
         - [ ] 5.4.4   POST /_matrix/client/r0/logout/all
         - [ ] 5.4.5   Login Fallback
diff --git a/src/api/client.rs b/src/api/client.rs
index 96af400..c64ace5 100644
--- a/src/api/client.rs
+++ b/src/api/client.rs
@@ -303,6 +303,8 @@ impl Client {
 // Holds implementation for Section 5.4, Login
 impl Client {
     /// Implementation of [Section 5.4.1 **GET** `/_matrix/client/r0/login`](https://matrix.org/docs/spec/client_server/r0.5.0#get-matrix-client-r0-login).
+    ///
+    /// This request is rate-limited but does not require authentication.
     pub fn login_flows(&self) -> Result<ValidLoginFlows, Box<dyn Error>> {
         Ok(self
             .send(
@@ -326,6 +328,8 @@ impl Client {
     ///
     /// You may specify a device display name if the provided device ID is not
     /// known. It is ignored if the device ID already exists.
+    ///
+    /// This request is rate-limited but does not require authentication.
     pub fn login_password(
         &self,
         identifier: IdentifierType,
@@ -355,6 +359,8 @@ impl Client {
     ///
     /// You may specify a device display name if the provided device ID is not
     /// known. It is ignored if the device ID already exists.
+    ///
+    /// This request is rate-limited but does not require authentication.
     pub fn login_token(
         &self,
         identifier: IdentifierType,
@@ -373,6 +379,9 @@ impl Client {
         )
     }
 
+    /// Actual method that performs the login request. Accepts a body that
+    /// should already be populated with the login-specific values needed for
+    /// that particular login type.
     fn login(
         &self,
         body: Value,
diff --git a/src/api/methods/login.rs b/src/api/methods/login.rs
index fed85fd..ac0961e 100644
--- a/src/api/methods/login.rs
+++ b/src/api/methods/login.rs
@@ -17,16 +17,16 @@ pub struct LoginFlow {
 /// Known identifier types for authentication methods. See [Section 5.3.6](https://matrix.org/docs/spec/client_server/r0.5.0#identifier-types)
 /// for more details.
 #[derive(Deserialize, Serialize)]
+#[serde(tag = "type")]
 pub enum IdentifierType {
     #[serde(rename = "m.id.user")]
-    User,
+    User { user: String },
     #[serde(rename = "m.id.thirdparty")]
-    ThirdParty,
+    ThirdParty { medium: String, address: String },
     #[serde(rename = "m.id.phone")]
-    Phone
+    Phone { country: String, phone: String },
 }
 
-
 /// Response for a valid login from 5.4.2: POST /_matrix/client/r0/login
 #[derive(Deserialize)]
 pub struct LoginResponse {