diff --git a/ethcore/src/client.rs b/ethcore/src/client.rs
index 32a24ddd6..03c03ab49 100644
--- a/ethcore/src/client.rs
+++ b/ethcore/src/client.rs
@@ -15,6 +15,7 @@ use service::NetSyncMessage;
 use env_info::LastHashes;
 use verification::*;
 use block::*;
+pub use blockchain::TreeRoute;
 
 /// General block status
 #[derive(Debug, Eq, PartialEq)]
@@ -50,8 +51,6 @@ impl fmt::Display for BlockChainInfo {
 	}
 }
 
-/// TODO [arkpar] Please document me
-pub type TreeRoute = ::blockchain::TreeRoute;
 
 /// Blockchain database client. Owns and manages a blockchain and a block queue.
 pub trait BlockChainClient : Sync + Send {
diff --git a/ethcore/src/ethereum/denominations.rs b/ethcore/src/ethereum/denominations.rs
index 093be89a7..dc06ceb58 100644
--- a/ethcore/src/ethereum/denominations.rs
+++ b/ethcore/src/ethereum/denominations.rs
@@ -1,22 +1,21 @@
 use util::*;
 
 #[inline]
-/// TODO [debris] Please document me
+/// 1 Ether in Wei
 pub fn ether() -> U256 { U256::exp10(18) }
 
-#[inline]
-/// TODO [debris] Please document me
+/// 1 Finney in Wei
 pub fn finney() -> U256 { U256::exp10(15) }
 
 #[inline]
-/// TODO [debris] Please document me
+/// 1 Szabo in Wei
 pub fn szabo() -> U256 { U256::exp10(12) }
 
 #[inline]
-/// TODO [debris] Please document me
+/// 1 Shannon in Wei
 pub fn shannon() -> U256 { U256::exp10(9) }
 
 #[inline]
-/// TODO [debris] Please document me
+/// 1 Wei in Wei
 pub fn wei() -> U256 { U256::exp10(0) }
 
diff --git a/ethcore/src/ethereum/ethash.rs b/ethcore/src/ethereum/ethash.rs
index 9cb0c5825..e9aedc128 100644
--- a/ethcore/src/ethereum/ethash.rs
+++ b/ethcore/src/ethereum/ethash.rs
@@ -21,7 +21,7 @@ pub struct Ethash {
 }
 
 impl Ethash {
-	/// TODO [arkpar] Please document me
+	/// Create a new boxed instance of Ethash engine
 	pub fn new_boxed(spec: Spec) -> Box<Engine> {
 		Box::new(Ethash {
 			spec: spec,
diff --git a/ethcore/src/evm/mod.rs b/ethcore/src/evm/mod.rs
index 1426bc281..2ed9a1146 100644
--- a/ethcore/src/evm/mod.rs
+++ b/ethcore/src/evm/mod.rs
@@ -2,7 +2,6 @@
 
 pub mod ext;
 pub mod evm;
-/// TODO [Tomusdrw] Please document me
 pub mod interpreter;
 #[macro_use]
 pub mod factory;
diff --git a/ethcore/src/extras.rs b/ethcore/src/extras.rs
index f3f3208ad..4c54c6b27 100644
--- a/ethcore/src/extras.rs
+++ b/ethcore/src/extras.rs
@@ -7,21 +7,21 @@ use rocksdb::{DB, Writable};
 /// Represents index of extra data in database
 #[derive(Copy, Debug, Hash, Eq, PartialEq, Clone)]
 pub enum ExtrasIndex {
-	/// TODO [debris] Please document me
+	/// Block details index
 	BlockDetails = 0,
-	/// TODO [debris] Please document me
+	/// Block hash index
 	BlockHash = 1,
-	/// TODO [debris] Please document me
+	/// Transaction address index
 	TransactionAddress = 2,
-	/// TODO [debris] Please document me
+	/// Block log blooms index
 	BlockLogBlooms = 3,
-	/// TODO [debris] Please document me
+	/// Block blooms index
 	BlocksBlooms = 4
 } 
 
 /// trait used to write Extras data to db
 pub trait ExtrasWritable {
-	/// TODO [debris] Please document me
+	/// Write extra data to db
 	fn put_extras<K, T>(&self, hash: &K, value: &T) where
 		T: ExtrasIndexable + Encodable, 
 		K: ExtrasSliceConvertable;
@@ -29,12 +29,12 @@ pub trait ExtrasWritable {
 
 /// trait used to read Extras data from db
 pub trait ExtrasReadable {
-	/// TODO [debris] Please document me
+	/// Read extra data from db
 	fn get_extras<K, T>(&self, hash: &K) -> Option<T> where
 		T: ExtrasIndexable + Decodable,
 		K: ExtrasSliceConvertable;
 
-	/// TODO [debris] Please document me
+	/// Check if extra data exists in the db
 	fn extras_exists<K, T>(&self, hash: &K) -> bool where
 		T: ExtrasIndexable,
 		K: ExtrasSliceConvertable;
@@ -98,7 +98,7 @@ impl ExtrasSliceConvertable for BlockNumber {
 
 /// Types implementing this trait can be indexed in extras database
 pub trait ExtrasIndexable {
-	/// TODO [debris] Please document me
+	/// Returns this data index
 	fn extras_index() -> ExtrasIndex;
 }
 
@@ -111,13 +111,13 @@ impl ExtrasIndexable for H256 {
 /// Familial details concerning a block
 #[derive(Debug, Clone)]
 pub struct BlockDetails {
-	/// TODO [debris] Please document me
+	/// Block number
 	pub number: BlockNumber,
-	/// TODO [debris] Please document me
+	/// Total difficulty of the block and all its parents
 	pub total_difficulty: U256,
-	/// TODO [debris] Please document me
+	/// Parent block hash
 	pub parent: H256,
-	/// TODO [debris] Please document me
+	/// List of children block hashes
 	pub children: Vec<H256>
 }
 
@@ -159,7 +159,7 @@ impl Encodable for BlockDetails {
 /// Log blooms of certain block
 #[derive(Clone)]
 pub struct BlockLogBlooms {
-	/// TODO [debris] Please document me
+	/// List of log blooms for the block
 	pub blooms: Vec<H2048>
 }
 
@@ -193,7 +193,7 @@ impl Encodable for BlockLogBlooms {
 
 /// Neighboring log blooms on certain level
 pub struct BlocksBlooms {
-	/// TODO [debris] Please document me
+	/// List of block blooms.
 	pub blooms: [H2048; 16]
 }
 
@@ -241,9 +241,9 @@ impl Encodable for BlocksBlooms {
 /// Represents address of certain transaction within block
 #[derive(Clone)]
 pub struct TransactionAddress {
-	/// TODO [debris] Please document me
+	/// Block hash
 	pub block_hash: H256,
-	/// TODO [debris] Please document me
+	/// Transaction index within the block
 	pub index: u64
 }
 
diff --git a/ethcore/src/service.rs b/ethcore/src/service.rs
index e12fc249f..fa530df70 100644
--- a/ethcore/src/service.rs
+++ b/ethcore/src/service.rs
@@ -15,7 +15,7 @@ pub enum SyncMessage {
 	BlockVerified,
 }
 
-/// TODO [arkpar] Please document me
+/// IO Message type used for Network service
 pub type NetSyncMessage = NetworkIoMessage<SyncMessage>;
 
 /// Client service setup. Creates and registers client and network services with the IO subsystem.
diff --git a/sync/src/service.rs b/sync/src/service.rs
deleted file mode 100644
index 8c900d20a..000000000
--- a/sync/src/service.rs
+++ /dev/null
@@ -1,104 +0,0 @@
-use util::*;
-use sync::*;
-use spec::Spec;
-use error::*;
-use std::env;
-use client::Client;
-
-/// Message type for external and internal events
-#[derive(Clone)]
-pub enum SyncMessage {
-	/// New block has been imported into the blockchain
-	NewChainBlock(Bytes), //TODO: use Cow
-	/// A block is ready 
-	BlockVerified,
-}
-
-/// TODO [arkpar] Please document me
-pub type NetSyncMessage = NetworkIoMessage<SyncMessage>;
-
-/// Client service setup. Creates and registers client and network services with the IO subsystem.
-pub struct ClientService {
-	net_service: NetworkService<SyncMessage>,
-	client: Arc<Client>,
-	sync: Arc<EthSync>,
-}
-
-impl ClientService {
-	/// Start the service in a separate thread.
-	pub fn start(spec: Spec, net_config: NetworkConfiguration) -> Result<ClientService, Error> {
-		let mut net_service = try!(NetworkService::start(net_config));
-		info!("Starting {}", net_service.host_info());
-		info!("Configured for {} using {} engine", spec.name, spec.engine_name);
-		let mut dir = env::home_dir().unwrap();
-		dir.push(".parity");
-		dir.push(H64::from(spec.genesis_header().hash()).hex());
-		let client = try!(Client::new(spec, &dir, net_service.io().channel()));
-		let sync = EthSync::register(&mut net_service, client.clone());
-		let client_io = Arc::new(ClientIoHandler {
-			client: client.clone()
-		});
-		try!(net_service.io().register_handler(client_io));
-
-		Ok(ClientService {
-			net_service: net_service,
-			client: client,
-			sync: sync,
-		})
-	}
-
-	/// Get the network service.
-	pub fn add_node(&mut self, _enode: &str) {
-		unimplemented!();
-	}
-
-	/// TODO [arkpar] Please document me
-	pub fn io(&mut self) -> &mut IoService<NetSyncMessage> {
-		self.net_service.io()
-	}
-
-	/// TODO [arkpar] Please document me
-	pub fn client(&self) -> Arc<Client> {
-		self.client.clone()
-	
-	}
-	
-	/// Get shared sync handler
-	pub fn sync(&self) -> Arc<EthSync> {
-		self.sync.clone()
-	}
-}
-
-/// IO interface for the Client handler
-struct ClientIoHandler {
-	client: Arc<Client>
-}
-
-const CLIENT_TICK_TIMER: TimerToken = 0;
-const CLIENT_TICK_MS: u64 = 5000;
-
-impl IoHandler<NetSyncMessage> for ClientIoHandler {
-	fn initialize(&self, io: &IoContext<NetSyncMessage>) {
-		io.register_timer(CLIENT_TICK_TIMER, CLIENT_TICK_MS).expect("Error registering client timer");
-	}
-
-	fn timeout(&self, _io: &IoContext<NetSyncMessage>, timer: TimerToken) {
-		if timer == CLIENT_TICK_TIMER {
-			self.client.tick();
-		}
-	}
-
-	#[allow(match_ref_pats)]
-	#[allow(single_match)]
-	fn message(&self, io: &IoContext<NetSyncMessage>, net_message: &NetSyncMessage) {
-		if let &UserMessage(ref message) = net_message {
-			match message {
-				&SyncMessage::BlockVerified => {
-					self.client.import_verified_blocks(&io.channel());
-				},
-				_ => {}, // ignore other messages
-			}
-		}
-	}
-}
-
diff --git a/util/src/bytes.rs b/util/src/bytes.rs
index f4937cafc..f6c83081d 100644
--- a/util/src/bytes.rs
+++ b/util/src/bytes.rs
@@ -111,11 +111,11 @@ impl ToPretty for Bytes {
 	}
 }
 
-/// TODO [debris] Please document me
+/// A byte collection reference that can either be a slice or a vector
 pub enum BytesRef<'a> {
-	/// TODO [debris] Please document me
+	/// This is a reference to a vector
 	Flexible(&'a mut Bytes),
-	/// TODO [debris] Please document me
+	/// This is a reference to a slice
 	Fixed(&'a mut [u8])
 }
 
diff --git a/util/src/chainfilter.rs b/util/src/chainfilter.rs
index 64f9e7d39..ad7f965dc 100644
--- a/util/src/chainfilter.rs
+++ b/util/src/chainfilter.rs
@@ -49,9 +49,9 @@ use sha3::*;
 /// index. Their `BloomIndex` can be created from block number and given level.
 #[derive(Eq, PartialEq, Hash, Clone, Debug)]
 pub struct BloomIndex {
-	/// TODO [debris] Please document me
+	/// Bloom level
 	pub level: u8,
-	/// TODO [debris] Please document me
+	///  Filter Index
 	pub index: usize,
 }
 
diff --git a/util/src/crypto.rs b/util/src/crypto.rs
index 845bb4798..0f147da1f 100644
--- a/util/src/crypto.rs
+++ b/util/src/crypto.rs
@@ -39,17 +39,17 @@ impl Signature {
 }
 
 #[derive(Debug)]
-/// TODO [arkpar] Please document me
+/// Crypto error
 pub enum CryptoError {
-	/// TODO [arkpar] Please document me
+	/// Invalid secret key
 	InvalidSecret,
-	/// TODO [arkpar] Please document me
+	/// Invalid public key
 	InvalidPublic,
-	/// TODO [arkpar] Please document me
+	/// Invalid EC signature
 	InvalidSignature,
-	/// TODO [arkpar] Please document me
+	/// Invalid AES message
 	InvalidMessage,
-	/// TODO [arkpar] Please document me
+	/// IO Error
 	Io(::std::io::Error),
 }
 
@@ -134,7 +134,7 @@ impl KeyPair {
 	pub fn sign(&self, message: &H256) -> Result<Signature, CryptoError> { ec::sign(&self.secret, message) }
 }
 
-/// TODO [arkpar] Please document me
+/// EC functions
 pub mod ec {
 	use hash::*;
 	use uint::*;
@@ -211,12 +211,12 @@ pub mod ec {
 	}
 }
 
-/// TODO [arkpar] Please document me
+/// ECDH functions
 pub mod ecdh {
 	use crypto::*;
 	use crypto::{self};
 
-	/// TODO [arkpar] Please document me
+	/// Agree on a shared secret
 	pub fn agree(secret: &Secret, public: &Public, ) -> Result<Secret, CryptoError> {
 		use secp256k1::*;
 		let context = &crypto::SECP256K1;
@@ -232,13 +232,13 @@ pub mod ecdh {
 	}
 }
 
-/// TODO [arkpar] Please document me
+/// ECIES function
 pub mod ecies {
 	use hash::*;
 	use bytes::*;
 	use crypto::*;
 
-	/// TODO [arkpar] Please document me
+	/// Encrypt a message with a public key
 	pub fn encrypt(public: &Public, plain: &[u8]) -> Result<Bytes, CryptoError> {
 		use ::rcrypto::digest::Digest;
 		use ::rcrypto::sha2::Sha256;
@@ -274,7 +274,7 @@ pub mod ecies {
 		Ok(msg)
 	}
 
-	/// TODO [arkpar] Please document me
+	/// Decrypt a message with a secret key
 	pub fn decrypt(secret: &Secret, encrypted: &[u8]) -> Result<Bytes, CryptoError> {
 		use ::rcrypto::digest::Digest;
 		use ::rcrypto::sha2::Sha256;
@@ -340,20 +340,20 @@ pub mod ecies {
 	}
 }
 
-/// TODO [arkpar] Please document me
+/// AES encryption
 pub mod aes {
 	use ::rcrypto::blockmodes::*;
 	use ::rcrypto::aessafe::*;
 	use ::rcrypto::symmetriccipher::*;
 	use ::rcrypto::buffer::*;
 
-	/// TODO [arkpar] Please document me
+	/// Encrypt a message
 	pub fn encrypt(k: &[u8], iv: &[u8], plain: &[u8], dest: &mut [u8]) {
 		let mut encryptor = CtrMode::new(AesSafe128Encryptor::new(k), iv.to_vec());
 		encryptor.encrypt(&mut RefReadBuffer::new(plain), &mut RefWriteBuffer::new(dest), true).expect("Invalid length or padding");
 	}
 
-	/// TODO [arkpar] Please document me
+	/// Decrypt a message
 	pub fn decrypt(k: &[u8], iv: &[u8], encrypted: &[u8], dest: &mut [u8]) {
 		let mut encryptor = CtrMode::new(AesSafe128Encryptor::new(k), iv.to_vec());
 		encryptor.decrypt(&mut RefReadBuffer::new(encrypted), &mut RefWriteBuffer::new(dest), true).expect("Invalid length or padding");
diff --git a/util/src/io/mod.rs b/util/src/io/mod.rs
index f81732ce1..e421416ee 100644
--- a/util/src/io/mod.rs
+++ b/util/src/io/mod.rs
@@ -42,9 +42,9 @@ mod worker;
 use mio::{EventLoop, Token};
 
 #[derive(Debug)]
-/// TODO [arkpar] Please document me
+/// IO Error
 pub enum IoError {
-	/// TODO [arkpar] Please document me
+	/// Low level error from mio crate
 	Mio(::std::io::Error),
 }
 
@@ -78,19 +78,12 @@ pub trait IoHandler<Message>: Send + Sync where Message: Send + Sync + Clone + '
 	fn deregister_stream(&self, _stream: StreamToken, _event_loop: &mut EventLoop<IoManager<Message>>) {}
 }
 
-/// TODO [arkpar] Please document me
 pub use io::service::TimerToken;
-/// TODO [arkpar] Please document me
 pub use io::service::StreamToken;
-/// TODO [arkpar] Please document me
 pub use io::service::IoContext;
-/// TODO [arkpar] Please document me
 pub use io::service::IoService;
-/// TODO [arkpar] Please document me
 pub use io::service::IoChannel;
-/// TODO [arkpar] Please document me
 pub use io::service::IoManager;
-/// TODO [arkpar] Please document me
 pub use io::service::TOKENS_PER_HANDLER;
 
 #[cfg(test)]
diff --git a/util/src/rlp/bytes.rs b/util/src/rlp/bytes.rs
index b61744977..aa7287462 100644
--- a/util/src/rlp/bytes.rs
+++ b/util/src/rlp/bytes.rs
@@ -140,9 +140,9 @@ impl <T>ToBytes for T where T: FixedHash {
 /// Error returned when FromBytes conversation goes wrong
 #[derive(Debug, PartialEq, Eq)]
 pub enum FromBytesError {
-	/// TODO [debris] Please document me
+	/// Expected more RLP data
 	DataIsTooShort,
-	/// TODO [debris] Please document me
+	/// Extra bytes after the end of the last item
 	DataIsTooLong,
 	/// Integer-representation is non-canonically prefixed with zero byte(s).
 	ZeroPrefixedInt,
@@ -165,7 +165,7 @@ pub type FromBytesResult<T> = Result<T, FromBytesError>;
 ///
 /// TODO: check size of bytes before conversation and return appropriate error
 pub trait FromBytes: Sized {
-	/// TODO [debris] Please document me
+	/// Create a value from bytes
 	fn from_bytes(bytes: &[u8]) -> FromBytesResult<Self>;
 }
 
diff --git a/util/src/rlp/rlpin.rs b/util/src/rlp/rlpin.rs
index cfcaee014..9b922ed43 100644
--- a/util/src/rlp/rlpin.rs
+++ b/util/src/rlp/rlpin.rs
@@ -103,12 +103,12 @@ impl <'a, 'view> Rlp<'a> where 'a: 'view {
 		res.unwrap_or_else(|_| panic!())
 	}
 
-	/// TODO [debris] Please document me
+	/// Decode into an object
 	pub fn as_val<T>(&self) -> T where T: RlpDecodable {
 		Self::view_as_val(self)
 	}
 
-	/// TODO [debris] Please document me
+	/// Decode list item at given index into an object
 	pub fn val_at<T>(&self, index: usize) -> T where T: RlpDecodable {
 		Self::view_as_val(&self.at(index))
 	}
diff --git a/util/src/rlp/rlptraits.rs b/util/src/rlp/rlptraits.rs
index c660fbe1e..f6b39729a 100644
--- a/util/src/rlp/rlptraits.rs
+++ b/util/src/rlp/rlptraits.rs
@@ -31,17 +31,17 @@ pub trait RlpDecodable: Sized {
 	fn decode<D>(decoder: &D) -> Result<Self, DecoderError>  where D: Decoder;
 }
 
-/// TODO [debris] Please document me
+/// A view into RLP encoded data
 pub trait View<'a, 'view>: Sized {
-	/// TODO [debris] Please document me
+	/// RLP prototype type
 	type Prototype;
-	/// TODO [debris] Please document me
+	/// Payload info type
 	type PayloadInfo;
-	/// TODO [debris] Please document me
+	/// Data type
 	type Data;
-	/// TODO [debris] Please document me
+	/// Item type
 	type Item;
-	/// TODO [debris] Please document me
+	/// Iterator type
 	type Iter;
 
 	/// Creates a new instance of `Rlp` reader
@@ -65,10 +65,10 @@ pub trait View<'a, 'view>: Sized {
 	/// Get the prototype of the RLP.
 	fn prototype(&self) -> Self::Prototype;
 
-	/// TODO [debris] Please document me
+	/// Get payload info.
 	fn payload_info(&self) -> Self::PayloadInfo;
 
-	/// TODO [debris] Please document me
+	/// Get underlieing data.
 	fn data(&'view self) -> Self::Data;
 
 	/// Returns number of RLP items.
@@ -205,18 +205,18 @@ pub trait View<'a, 'view>: Sized {
 	/// ```
 	fn iter(&'view self) -> Self::Iter;
 
-	/// TODO [debris] Please document me
+	/// Decode data into an object
 	fn as_val<T>(&self) -> Result<T, DecoderError> where T: RlpDecodable;
 
-	/// TODO [debris] Please document me
+	/// Decode data at given list index into an object
 	fn val_at<T>(&self, index: usize) -> Result<T, DecoderError> where T: RlpDecodable;
 }
 
-/// TODO [debris] Please document me
+/// Raw RLP encoder
 pub trait Encoder {
-	/// TODO [debris] Please document me
+	/// Write a value represented as bytes
 	fn emit_value<E: ByteEncodable>(&mut self, value: &E);
-	/// TODO [debris] Please document me
+	/// Write raw preencoded data to the output
 	fn emit_raw(&mut self, bytes: &[u8]) -> ();
 }
 
@@ -250,7 +250,7 @@ pub trait RlpEncodable {
 	fn rlp_append(&self, s: &mut RlpStream);
 }
 
-/// TODO [debris] Please document me
+/// RLP encoding stream
 pub trait Stream: Sized {
 
 	/// Initializes instance of empty `Stream`.
@@ -341,7 +341,7 @@ pub trait Stream: Sized {
 	/// }
 	fn is_finished(&self) -> bool;
 
-	/// TODO [debris] Please document me
+	/// Get raw encoded bytes
 	fn as_raw(&self) -> &[u8];
 
 	/// Streams out encoded bytes.
diff --git a/util/src/rlp/untrusted_rlp.rs b/util/src/rlp/untrusted_rlp.rs
index 604273b20..ed288bbdd 100644
--- a/util/src/rlp/untrusted_rlp.rs
+++ b/util/src/rlp/untrusted_rlp.rs
@@ -21,21 +21,21 @@ impl OffsetCache {
 }
 
 #[derive(Debug)]
-/// TODO [debris] Please document me
+/// RLP prototype
 pub enum Prototype {
-	/// TODO [debris] Please document me
+	/// Empty
 	Null,
-	/// TODO [debris] Please document me
+	/// Value
 	Data(usize),
-	/// TODO [debris] Please document me
+	/// List
 	List(usize),
 }
 
 /// Stores basic information about item
 pub struct PayloadInfo {
-	/// TODO [debris] Please document me
+	/// Header length in bytes
 	pub header_len: usize,
-	/// TODO [debris] Please document me
+	/// Value length in bytes
 	pub value_len: usize,
 }
 
diff --git a/util/src/squeeze.rs b/util/src/squeeze.rs
index 3fb4a81f9..5cda39249 100644
--- a/util/src/squeeze.rs
+++ b/util/src/squeeze.rs
@@ -36,7 +36,7 @@ use heapsize::HeapSizeOf;
 
 /// Should be used to squeeze collections to certain size in bytes
 pub trait Squeeze {
-	/// TODO [debris] Please document me
+	/// Try to reduce collection size to `size` bytes
 	fn squeeze(&mut self, size: usize);
 }
 
diff --git a/util/src/vector.rs b/util/src/vector.rs
index b9770e30b..ed844a5a4 100644
--- a/util/src/vector.rs
+++ b/util/src/vector.rs
@@ -13,7 +13,7 @@
 ///	}
 /// ```
 pub trait SharedPrefix <T> {
-	/// TODO [debris] Please document me
+	/// Get common prefix length
 	fn shared_prefix_len(&self, elem: &[T]) -> usize;
 }