diff --git a/README.md b/README.md
index 5fbd213..65a486b 100644
--- a/README.md
+++ b/README.md
@@ -535,7 +535,7 @@ usage: grammar_file_path [source_file_path]
 
   options:
     --ast: show AST tree
-    --opt: optimaze all AST nodes except nodes selected with --opt-rules
+    --opt, --opt-all: optimaze all AST nodes except nodes selected with --opt-rules
     --opt-only: optimaze only AST nodes selected with --opt-rules
     --opt-rules rules: comma delimitted definition rules for optimazation
     --source: source text
@@ -612,6 +612,30 @@ Number      <- < [0-9]+ >
     - Multitive[Number] (3)
 ```
 
+```
+> peglint --ast --opt --opt-rules "Primary" --source "1 + 2 * 3" a.peg
++ Additive/0
+  + Multitive/1[Primary]
+    - Number (1)
+  + Additive/1[Multitive]
+    + Primary/1
+      - Number (2)
+    + Multitive/1[Primary]
+      - Number (3)
+```
+
+```
+> peglint --ast --opt-only --opt-rules "Primary" --source "1 + 2 * 3" a.peg
++ Additive/0
+  + Multitive/1
+    - Primary/1[Number] (1)
+  + Additive/1
+    + Multitive/0
+      - Primary/1[Number] (2)
+      + Multitive/1
+        - Primary/1[Number] (3)
+```
+
 Sample codes
 ------------
 
diff --git a/lint/README.md b/lint/README.md
index 7300fe4..ef55c0a 100644
--- a/lint/README.md
+++ b/lint/README.md
@@ -4,5 +4,117 @@ peglint
 The lint utility for PEG.
 
 ```
-usage: peglint [--ast] [--optimize_ast_nodes|--opt] [--trace] [grammar file path] [source file path]
+usage: grammar_file_path [source_file_path]
+
+  options:
+    --ast: show AST tree
+    --opt, --opt-all: optimaze all AST nodes except nodes selected with --opt-rules
+    --opt-only: optimaze only AST nodes selected with --opt-rules
+    --opt-rules rules: comma delimitted definition rules for optimazation
+    --source: source text
+    --trace: show trace messages
+```
+
+### Build peglint
+
+```
+> cd lint
+> mkdir build
+> cd build
+> cmake ..
+> make
+```
+
+### Lint grammar
+
+```
+> cat a.peg
+A <- 'hello' ^ 'world'
+
+> peglint a.peg
+a.peg:1:14: syntax error
+```
+
+```
+> cat a.peg
+A <- B
+
+> peglint a.peg
+a.peg:1:6: 'B' is not defined.
+```
+
+```
+> cat a.peg
+A <- B / C
+B <- 'b'
+C <- A
+
+> peglint a.peg
+a.peg:1:10: 'C' is left recursive.
+a.peg:3:6: 'A' is left recursive.
+```
+
+### Lint source text
+
+```
+> cat a.peg
+Additive    <- Multitive '+' Additive / Multitive
+Multitive   <- Primary '*' Multitive / Primary
+Primary     <- '(' Additive ')' / Number
+Number      <- < [0-9]+ >
+%whitespace <- [ \t\r\n]*
+
+> peglint --source "1 + a * 3" a.peg
+[commendline]:1:3: syntax error
+```
+
+```
+> cat a.txt
+1 + 2 * 3
+
+> peglint --ast a.peg a.txt
++ Additive
+  + Multitive
+    + Primary
+      - Number (1)
+  + Additive
+    + Multitive
+      + Primary
+        - Number (2)
+      + Multitive
+        + Primary
+          - Number (3)
+```
+
+```
+> peglint --ast --opt --source "1 + 2 * 3" a.peg
++ Additive
+  - Multitive[Number] (1)
+  + Additive[Multitive]
+    - Primary[Number] (2)
+    - Multitive[Number] (3)
+```
+
+```
+> peglint --ast --opt --opt-rules "Primary" --source "1 + 2 * 3" a.peg
++ Additive/0
+  + Multitive/1[Primary]
+    - Number (1)
+  + Additive/1[Multitive]
+    + Primary/1
+      - Number (2)
+    + Multitive/1[Primary]
+      - Number (3)
+```
+
+```
+> peglint --ast --opt-only --opt-rules "Primary" --source "1 + 2 * 3" a.peg
++ Additive/0
+  + Multitive/1
+    - Primary/1[Number] (1)
+  + Additive/1
+    + Multitive/0
+      - Primary/1[Number] (2)
+      + Multitive/1
+        - Primary/1[Number] (3)
 ```
diff --git a/lint/peglint.cc b/lint/peglint.cc
index f8a77ff..930fd2e 100644
--- a/lint/peglint.cc
+++ b/lint/peglint.cc
@@ -50,7 +50,7 @@ int main(int argc, const char **argv) {
       opt_help = true;
     } else if (string("--ast") == arg) {
       opt_ast = true;
-    } else if (string("--opt-all") == arg) {
+    } else if (string("--opt") == arg || string("--opt-all") == arg) {
       opt_optimize = true;
       opt_mode = true;
     } else if (string("--opt-only") == arg) {
@@ -80,7 +80,8 @@ int main(int argc, const char **argv) {
          << "  options:" << endl
          << "    --source: source text" << endl
          << "    --ast: show AST tree" << endl
-         << "    --opt-all: optimaze all AST nodes except nodes selected with "
+         << "    --opt, --opt-all: optimaze all AST nodes except nodes "
+            "selected with "
             "--opt-rules"
          << endl
          << "    --opt-only: optimaze only AST nodes selected with --opt-rules"