docs(api): Fill in missing doc comments

src/api/mod.rs

@@ -12,12 +12,28 @@ use responses::{
 pub mod endpoints;
 pub mod responses;
 
+/// An API client used for interfacing with a specific CT log. This can be
+/// constructed with [`CtApiClient::new`] to automatically create an inner
+/// [`reqwest::Client`], or an [`Arc`] of one can be passed manually with
+/// [`CtApiClient::new_with_client`] to re-use an existing client between code.
+/// Re-using clients if one is already created is recommended, as it allows
+/// connection-pools to be re-used and will have less overhead between requests.
 pub struct CtApiClient {
 	inner_client: Arc<reqwest::Client>,
 	log_url: Url
 }
 
 impl CtApiClient {
+	/// Creates a new [`CtApiClient`] given a specific log URL. This log URL can
+	/// contain a subpath if the specific log uses one. Anything besides a
+	/// scheme, host information (ip/port), and a standard path is not supported
+	/// and will likely cause requests to fail.
+	///
+	/// ## Errors
+	///
+	/// As this automatically constructs a [`reqwest::Client`], this will error
+	/// if the client fails to be created for whatever reason, usually due to it
+	/// being unable to find TLS configuration and root store for the platform.
 	pub fn new(log_url: Url) -> reqwest::Result<Self> {
 		Ok(Self {
 			inner_client: Arc::new(reqwest::Client::builder().https_only(true).build()?),
@@ -25,6 +41,11 @@ impl CtApiClient {
 		})
 	}
 
+	/// Creates a new [`CtApiClient`] given a specific log URL and
+	/// [`reqwest::Client`]. This log URL can contain a subpath if the specific
+	/// log uses one. Anything besides a scheme, host information (ip/port),
+	/// and a standard path is not supported and will likely cause requests to
+	/// fail.
 	pub fn new_with_client(log_url: Url, inner_client: Arc<reqwest::Client>) -> Self {
 		Self {
 			inner_client,