diff --git a/README.md b/README.md
index 67f7136..b62f92f 100644
--- a/README.md
+++ b/README.md
@@ -5,7 +5,7 @@ Collection of WASM utilities used in Parity and WASM contract devepment
 ## Symbols optimizer (wasm-opt)
 
 ```
-cargo run --release --bin wasm-opt -- <contract.wasm>
+cargo run --release --bin wasm-opt -- <input_binary.wasm> <output_binary.wasm>
 ```
 
 This will optimize WASM symbols tree to leave only those elements that are used by contract `call` function entry.
@@ -15,11 +15,17 @@ This will optimize WASM symbols tree to leave only those elements that are used
 For development puposes, raw WASM contract can be injected with gas counters (the same way as it done by Parity runtime when running contracts)
 
 ```
-cargo run --release --bin wasm-gas -- <contract
+cargo run --release --bin wasm-gas -- <input_binary.wasm> <output_binary.wasm>
 ```
 
 ## Allocators substiution (wasm-ext)
 
 Parity WASM runtime provides simple memory allocators, if contract requires. When relied on this allocators, WASM binary size can be greatly reduce. This utility scans for `_malloc`, `_free` invokes inside the WASM binary and substitutes it with invokes of the imported `_malloc`, `_free`. Should be run before `wasm-opt` for better results.
 
+```
+cargo run --release --bin wasm-ext -- <input_binary.wasm> <output_binary.wasm>
+```
+
+## API
+
 All executables use corresponding api methods in the root crate and can be combined in other build tools.