Added missing "Errors" and "Panics" sections to request.rs and response.rs

src/request.rs

@@ -153,6 +153,11 @@ impl RequestBuilder {
     /// # Ok(())
     /// # }
     /// ```
+    ///
+    /// # Errors
+    ///
+    /// This method fails if the passed value cannot be serialized into
+    /// url encoded format
     pub fn form<T: Serialize>(&mut self, form: &T) -> ::Result<&mut RequestBuilder> {
         {
             // check request_mut() before running serde
@@ -202,6 +207,11 @@ impl RequestBuilder {
 
     /// Build a `Request`, which can be inspected, modified and executed with
     /// `Client::execute()`.
+    ///
+    /// # Panics
+    ///
+    /// This method consumes builder internal state. It panics on an attempt to
+    /// reuse already consumed builder.
     pub fn build(&mut self) -> Request {
         self.request
             .take()
@@ -209,6 +219,11 @@ impl RequestBuilder {
     }
 
     /// Constructs the Request and sends it the target URL, returning a Response.
+    ///
+    /// # Errors
+    ///
+    /// This method fails if there was an error while sending request,
+    /// redirect loop was detected or redirect limit was exhausted.
     pub fn send(&mut self) -> ::Result<::Response> {
         let request = self.build();
         self.client.execute(request)

src/response.rs

@@ -100,6 +100,13 @@ impl Response {
     /// #     }
     /// # }
     /// ```
+    ///
+    /// # Errors
+    ///
+    /// This method fails whenever the response body is not in JSON format
+    /// or it cannot be properly deserialized to target type `T`. For more
+    /// details please see [`serde_json::from_reader`].
+    /// [`serde_json::from_reader`]: https://docs.serde.rs/serde_json/fn.from_reader.html
     #[inline]
     pub fn json<T: DeserializeOwned>(&mut self) -> ::Result<T> {
         serde_json::from_reader(self).map_err(::error::from)