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cumulus/polkadot-parachain/polkadot-parachain-lib/src/cli.rs

@@ -119,7 +119,11 @@ pub struct Cli<Config: CliConfig> {
 	#[command(flatten)]
 	pub run: cumulus_client_cli::RunCmd,
 
-	/// Dev option for producing a block each `dev_block_time` ms.
+	/// Start a dev node that produces a block each `dev_block_time` ms.
+	///
+	/// This is a dev option, and it won't result in starting or connecting to a parachain network.
+	/// The resulting node will work on its own, running the wasm blob and artificially producing
+	/// a block each `dev_block_time` ms, as if it was part of a parachain.
 	#[arg(long)]
 	pub dev_block_time: Option<u64>,
 

cumulus/polkadot-parachain/polkadot-parachain-lib/src/nodes/mod.rs

@@ -23,6 +23,10 @@ use cumulus_primitives_core::ParaId;
 use manual_seal::ManualSealNode;
 use sc_service::{Configuration, TaskManager};
 
+/// Trait that extends the `DynNodeSpec` trait with manual seal related logic.
+///
+/// We need it in order to be able to access both the `DynNodeSpec` and the manual seal logic
+/// through dynamic dispatch.
 pub trait DynNodeSpecExt: DynNodeSpec {
 	fn start_manual_seal_node(
 		&self,