diff --git a/tonic/src/body.rs b/tonic/src/body.rs
index b9be632..d04848f 100644
--- a/tonic/src/body.rs
+++ b/tonic/src/body.rs
@@ -1,10 +1,13 @@
 use crate::{Error, Status};
 use bytes::{Buf, Bytes, IntoBuf};
 use http_body::Body as HttpBody;
-use std::pin::Pin;
-use std::task::{Context, Poll};
+use std::{
+    fmt,
+    pin::Pin,
+    task::{Context, Poll},
+};
 
-pub type BytesBuf = <Bytes as IntoBuf>::Buf;
+pub(crate) type BytesBuf = <Bytes as IntoBuf>::Buf;
 
 pub trait Body: sealed::Sealed {
     type Data: Buf;
@@ -61,6 +64,7 @@ mod sealed {
     pub trait Sealed {}
 }
 
+/// A type erased http body.
 pub struct BoxBody {
     inner: Pin<Box<dyn Body<Data = BytesBuf, Error = Status> + Send + 'static>>,
 }
@@ -158,3 +162,9 @@ where
         Poll::Ready(v)
     }
 }
+
+impl fmt::Debug for BoxBody {
+    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
+        f.debug_struct("BoxBody").finish()
+    }
+}
diff --git a/tonic/src/codec/prost.rs b/tonic/src/codec/prost.rs
index 365f1a0..776c907 100644
--- a/tonic/src/codec/prost.rs
+++ b/tonic/src/codec/prost.rs
@@ -40,6 +40,7 @@ where
 }
 
 /// A [`Encoder`] that knows how to encode `T`.
+#[derive(Debug, Clone)]
 pub struct ProstEncoder<T>(PhantomData<T>);
 
 impl<T: Message> Encoder for ProstEncoder<T> {
@@ -59,6 +60,7 @@ impl<T: Message> Encoder for ProstEncoder<T> {
 }
 
 /// A [`Decoder`] that knows how to decode `U`.
+#[derive(Debug, Clone)]
 pub struct ProstDecoder<U>(PhantomData<U>);
 
 impl<U: Message + Default> Decoder for ProstDecoder<U> {
diff --git a/tonic/src/error.rs b/tonic/src/error.rs
index ec8f9e5..8b3e873 100644
--- a/tonic/src/error.rs
+++ b/tonic/src/error.rs
@@ -1,10 +1,8 @@
 use std::fmt;
 
-#[allow(dead_code)]
 pub type Error = Box<dyn std::error::Error + Send + Sync>;
 
 #[derive(Debug)]
-#[allow(dead_code)]
 pub enum Never {}
 
 impl fmt::Display for Never {
diff --git a/tonic/src/lib.rs b/tonic/src/lib.rs
index fc60bf5..ce14853 100644
--- a/tonic/src/lib.rs
+++ b/tonic/src/lib.rs
@@ -1,4 +1,5 @@
 #![recursion_limit = "512"]
+#![warn(missing_debug_implementations)]
 
 //! gRPC implementation
 
@@ -17,7 +18,7 @@ mod request;
 mod response;
 mod status;
 
-#[doc(inline)]
+#[doc(inline, hidden)]
 pub use body::BoxBody;
 pub use request::Request;
 pub use response::Response;
@@ -27,7 +28,6 @@ pub use tonic_macros::{client, server};
 pub(crate) use error::Error;
 
 #[doc(hidden)]
-
 pub mod _codegen {
     pub use futures_core::Stream;
     pub use futures_util::future::{ok, poll_fn, Ready};
diff --git a/tonic/src/request.rs b/tonic/src/request.rs
index 529c007..b603db4 100644
--- a/tonic/src/request.rs
+++ b/tonic/src/request.rs
@@ -1,5 +1,6 @@
 use crate::metadata::MetadataMap;
 
+/// A gRPC request and metadata from an RPC call.
 #[derive(Debug)]
 pub struct Request<T> {
     metadata: MetadataMap,
diff --git a/tonic/src/response.rs b/tonic/src/response.rs
index 63e06a7..e6579d6 100644
--- a/tonic/src/response.rs
+++ b/tonic/src/response.rs
@@ -75,7 +75,4 @@ impl<T> Response<T> {
             message,
         }
     }
-
-    // pub fn metadata()
-    // pub fn metadata_bin()
 }
diff --git a/tonic/src/status.rs b/tonic/src/status.rs
index 519b75f..a6f63cb 100644
--- a/tonic/src/status.rs
+++ b/tonic/src/status.rs
@@ -1,8 +1,5 @@
-#![allow(dead_code)]
-
 use bytes::Bytes;
-use http::header::HeaderValue;
-use http::{self, HeaderMap};
+use http::header::{HeaderMap, HeaderValue};
 use percent_encoding::{percent_decode, percent_encode, EncodeSet, DEFAULT_ENCODE_SET};
 use std::{error::Error, fmt};
 use tracing::{debug, trace, warn};
@@ -60,22 +57,7 @@ impl Status {
         }
     }
 
-    // Deprecated: this constructor encourages creating statuses with no
-    // message, hurting later debugging.
-    #[doc(hidden)]
-    #[deprecated(note = "use State::new")]
-    pub fn with_code(code: Code) -> Status {
-        Status::new(code, String::new())
-    }
-
-    // Deprecated: this constructor is overly long.
-    #[doc(hidden)]
-    #[deprecated(note = "use State::new")]
-    pub fn with_code_and_message(code: Code, message: String) -> Status {
-        Status::new(code, message)
-    }
-
-    // FIXME: This should probably be made public eventually. Need to decide on
+    // TODO: This should probably be made public eventually. Need to decide on
     // the exact argument type.
     #[cfg_attr(not(feature = "h2"), allow(dead_code))]
     pub(crate) fn from_error(err: &(dyn Error + 'static)) -> Status {
@@ -107,6 +89,7 @@ impl Status {
         None
     }
 
+    // TODO: bubble this into `transport` and expose generic http2 reasons.
     #[cfg(feature = "h2")]
     fn from_h2_error(err: &h2::Error) -> Status {
         // See https://github.com/grpc/grpc/blob/3977c30/doc/PROTOCOL-HTTP2.md#errors
@@ -195,18 +178,6 @@ impl Status {
         &self.details
     }
 
-    #[doc(hidden)]
-    #[deprecated(note = "use Status::message")]
-    pub fn error_message(&self) -> &str {
-        &self.message
-    }
-
-    #[doc(hidden)]
-    #[deprecated(note = "use Status::details")]
-    pub fn binary_error_details(&self) -> &Bytes {
-        &self.details
-    }
-
     pub(crate) fn to_header_map(&self) -> Result<HeaderMap, Self> {
         let mut header_map = HeaderMap::with_capacity(3);
         self.add_header(&mut header_map)?;
@@ -409,7 +380,6 @@ impl Code {
         }
     }
 
-    #[allow(dead_code)]
     fn parse_err() -> Code {
         trace!("error parsing grpc-status");
         Code::Unknown
diff --git a/tonic/src/transport/channel.rs b/tonic/src/transport/channel.rs
index 778fc8b..e7df044 100644
--- a/tonic/src/transport/channel.rs
+++ b/tonic/src/transport/channel.rs
@@ -6,9 +6,12 @@ use crate::{client::GrpcService, BoxBody};
 use futures_util::try_future::{MapErr, TryFutureExt};
 use http::Uri;
 use hyper::{Request, Response};
-use std::future::Future;
-use std::pin::Pin;
-use std::task::{Context, Poll};
+use std::{
+    fmt,
+    future::Future,
+    pin::Pin,
+    task::{Context, Poll},
+};
 use tower_balance::p2c::Balance;
 use tower_buffer::{future::ResponseFuture, Buffer};
 use tower_discover::Discover;
@@ -114,3 +117,9 @@ impl Builder {
         self.balance_list(vec![uri.into()])
     }
 }
+
+impl fmt::Debug for Channel {
+    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
+        f.debug_struct("Channel").finish()
+    }
+}
diff --git a/tonic/src/transport/server.rs b/tonic/src/transport/server.rs
index 27815d7..ce3a029 100644
--- a/tonic/src/transport/server.rs
+++ b/tonic/src/transport/server.rs
@@ -12,6 +12,7 @@ use std::task::{Context, Poll};
 use tower_make::MakeService;
 use tower_service::Service;
 
+#[derive(Debug)]
 pub struct Server {}
 
 impl Server {
@@ -20,6 +21,7 @@ impl Server {
     }
 }
 
+#[derive(Debug)]
 pub struct Builder {
     tls: Option<(Vec<u8>, Vec<u8>)>,
 }
diff --git a/tonic/src/transport/service/connect.rs b/tonic/src/transport/service/connect.rs
index 96c7a75..67d8072 100644
--- a/tonic/src/transport/service/connect.rs
+++ b/tonic/src/transport/service/connect.rs
@@ -3,9 +3,12 @@ use crate::{transport::Endpoint, BoxBody};
 use http::{Request, Response, Uri};
 use hyper::client::conn::Builder;
 use hyper::client::service::Connect as HyperConnect;
-use std::future::Future;
-use std::pin::Pin;
-use std::task::{Context, Poll};
+use std::{
+    fmt,
+    future::Future,
+    pin::Pin,
+    task::{Context, Poll},
+};
 use tower_load::Load;
 use tower_reconnect::Reconnect;
 use tower_service::Service;
@@ -51,3 +54,9 @@ impl Load for Connection {
         0
     }
 }
+
+impl fmt::Debug for Connection {
+    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
+        f.debug_struct("Connection").finish()
+    }
+}