diff --git a/db/src/write_batch.rs b/db/src/write_batch.rs
index 0d6f174e42..ceb46c87b0 100644
--- a/db/src/write_batch.rs
+++ b/db/src/write_batch.rs
@@ -1,14 +1,17 @@
+//! TODO(doc): @quake
 use crate::db::cf_handle;
 use crate::{internal_error, Col, Result};
 use rocksdb::{OptimisticTransactionDB, WriteBatch};
 use std::sync::Arc;
 
+/// TODO(doc): @quake
 pub struct RocksDBWriteBatch {
     pub(crate) db: Arc<OptimisticTransactionDB>,
     pub(crate) inner: WriteBatch,
 }
 
 impl RocksDBWriteBatch {
+    /// TODO(doc): @quake
     pub fn len(&self) -> usize {
         self.inner.len()
     }
@@ -18,15 +21,18 @@ impl RocksDBWriteBatch {
         self.inner.size_in_bytes()
     }
 
+    /// TODO(doc): @quake
     pub fn is_empty(&self) -> bool {
         self.inner.is_empty()
     }
 
+    /// TODO(doc): @quake
     pub fn put(&mut self, col: Col, key: &[u8], value: &[u8]) -> Result<()> {
         let cf = cf_handle(&self.db, col)?;
         self.inner.put_cf(cf, key, value).map_err(internal_error)
     }
 
+    /// TODO(doc): @quake
     pub fn delete(&mut self, col: Col, key: &[u8]) -> Result<()> {
         let cf = cf_handle(&self.db, col)?;
         self.inner.delete_cf(cf, key).map_err(internal_error)
@@ -44,6 +50,7 @@ impl RocksDBWriteBatch {
             .map_err(internal_error)
     }
 
+    /// TODO(doc): @quake
     pub fn clear(&mut self) -> Result<()> {
         self.inner.clear().map_err(internal_error)
     }
diff --git a/spec/src/consensus.rs b/spec/src/consensus.rs
index 49e17e4cd4..e70e67aca0 100644
--- a/spec/src/consensus.rs
+++ b/spec/src/consensus.rs
@@ -69,6 +69,7 @@ pub(crate) const DEFAULT_PRIMARY_EPOCH_REWARD_HALVING_INTERVAL: EpochNumber =
 /// TODO(doc): @zhangsoledad
 pub const MAX_BLOCK_BYTES: u64 = TWO_IN_TWO_OUT_BYTES * TWO_IN_TWO_OUT_COUNT;
 pub(crate) const MAX_BLOCK_CYCLES: u64 = TWO_IN_TWO_OUT_CYCLES * TWO_IN_TWO_OUT_COUNT;
+/// TODO(doc): @zhangsoledad
 // 1.5 * TWO_IN_TWO_OUT_COUNT
 pub const MAX_BLOCK_PROPOSALS_LIMIT: u64 = 1_500;
 const PROPOSER_REWARD_RATIO: Ratio = Ratio(4, 10);
diff --git a/spec/src/lib.rs b/spec/src/lib.rs
index c259e2c243..eb1414b01c 100644
--- a/spec/src/lib.rs
+++ b/spec/src/lib.rs
@@ -120,6 +120,7 @@ pub mod default_params {
         GENESIS_EPOCH_LENGTH
     }
 
+    /// TODO(doc): @zhangsoledad
     pub fn max_block_proposals_limit() -> u64 {
         MAX_BLOCK_PROPOSALS_LIMIT
     }
@@ -155,6 +156,7 @@ pub struct Params {
     /// TODO(doc): @zhangsoledad
     #[serde(default)]
     pub permanent_difficulty_in_dummy: bool,
+    /// TODO(doc): @zhangsoledad
     #[serde(default = "default_params::max_block_proposals_limit")]
     pub max_block_proposals_limit: u64,
 }
diff --git a/store/src/write_batch.rs b/store/src/write_batch.rs
index 5af8a14392..af486fb7ec 100644
--- a/store/src/write_batch.rs
+++ b/store/src/write_batch.rs
@@ -4,15 +4,18 @@ use ckb_db::RocksDBWriteBatch;
 use ckb_error::Error;
 use ckb_types::{packed, prelude::*};
 
+/// TODO(doc): @quake
 pub struct StoreWriteBatch {
     pub(crate) inner: RocksDBWriteBatch,
 }
 
 impl StoreWriteBatch {
+    /// TODO(doc): @quake
     pub fn put(&mut self, col: Col, key: &[u8], value: &[u8]) -> Result<(), Error> {
         self.inner.put(col, key, value)
     }
 
+    /// TODO(doc): @quake
     pub fn delete(&mut self, col: Col, key: &[u8]) -> Result<(), Error> {
         self.inner.delete(col, key)
     }
@@ -22,18 +25,22 @@ impl StoreWriteBatch {
         self.inner.size_in_bytes()
     }
 
+    /// TODO(doc): @quake
     pub fn len(&self) -> usize {
         self.inner.len()
     }
 
+    /// TODO(doc): @quake
     pub fn is_empty(&self) -> bool {
         self.inner.is_empty()
     }
 
+    /// TODO(doc): @quake
     pub fn clear(&mut self) -> Result<(), Error> {
         self.inner.clear()
     }
 
+    /// TODO(doc): @quake
     pub fn insert_cells(
         &mut self,
         cells: impl Iterator<
@@ -56,6 +63,7 @@ impl StoreWriteBatch {
         Ok(())
     }
 
+    /// TODO(doc): @quake
     pub fn delete_cells(
         &mut self,
         out_points: impl Iterator<Item = packed::OutPoint>,
diff --git a/util/app-config/src/args.rs b/util/app-config/src/args.rs
index 1af2347a81..ad0226eb03 100644
--- a/util/app-config/src/args.rs
+++ b/util/app-config/src/args.rs
@@ -148,6 +148,8 @@ pub struct PeerIDArgs {
     pub peer_id: secio::PeerId,
 }
 
+/// TODO(doc): @doitian
 pub struct MigrateArgs {
+    /// TODO(doc): @doitian
     pub config: Box<CKBAppConfig>,
 }
diff --git a/util/app-config/src/cli.rs b/util/app-config/src/cli.rs
index a98875fcfe..72546d354e 100644
--- a/util/app-config/src/cli.rs
+++ b/util/app-config/src/cli.rs
@@ -27,6 +27,7 @@ pub const CMD_PEERID: &str = "peer-id";
 pub const CMD_GEN_SECRET: &str = "gen";
 /// TODO(doc): @doitian
 pub const CMD_FROM_SECRET: &str = "from-secret";
+/// TODO(doc): @doitian
 pub const CMD_MIGRATE: &str = "migrate";
 
 /// TODO(doc): @doitian