diff --git a/crates/bashkit/src/builtins/rg.rs b/crates/bashkit/src/builtins/rg.rs
index 765268cb..50aa7ce3 100644
--- a/crates/bashkit/src/builtins/rg.rs
+++ b/crates/bashkit/src/builtins/rg.rs
@@ -5,7 +5,7 @@
 //! Usage:
 //!   rg PATTERN [PATH...]
 //!   rg -i PATTERN file          # case insensitive
-//!   rg -n PATTERN file          # show line numbers (default)
+//!   rg -n PATTERN file          # show line numbers (off by default in non-tty)
 //!   rg -c PATTERN file          # count matches
 //!   rg -l PATTERN file          # files with matches
 //!   rg -v PATTERN file          # invert match
@@ -46,7 +46,7 @@ impl RgOptions {
             pattern: String::new(),
             paths: Vec::new(),
             ignore_case: false,
-            line_numbers: true, // rg shows line numbers by default
+            line_numbers: false, // non-tty: suppress line numbers (real rg behavior)
             count_only: false,
             files_with_matches: false,
             invert_match: false,
@@ -68,6 +68,7 @@ impl RgOptions {
                     match chars[j] {
                         'i' => opts.ignore_case = true,
                         'n' => opts.line_numbers = true,
+                        'N' => opts.line_numbers = false,
                         'c' => opts.count_only = true,
                         'l' => opts.files_with_matches = true,
                         'v' => opts.invert_match = true,
@@ -89,6 +90,8 @@ impl RgOptions {
                     // no-op
                 } else if opt == "no-line-number" {
                     opts.line_numbers = false;
+                } else if opt == "line-number" {
+                    opts.line_numbers = true;
                 }
                 // ignore other long options
             } else {
@@ -472,7 +475,8 @@ mod tests {
     }
 
     #[tokio::test]
-    async fn test_rg_line_numbers_default() {
+    async fn test_rg_no_line_numbers_default() {
+        // Non-tty: line numbers suppressed by default (like real rg)
         let result = run_rg(
             &["world", "/test.txt"],
             None,
@@ -480,7 +484,68 @@ mod tests {
         )
         .await;
         assert_eq!(result.exit_code, 0);
-        // Line numbers on by default, "world" is on line 2
-        assert!(result.stdout.contains("2:"));
+        assert_eq!(result.stdout.trim(), "world");
+        assert!(!result.stdout.contains("2:"));
+    }
+
+    #[tokio::test]
+    async fn test_rg_line_numbers_explicit() {
+        // -n flag enables line numbers
+        let result = run_rg(
+            &["-n", "world", "/test.txt"],
+            None,
+            &[("/test.txt", b"hello\nworld\n")],
+        )
+        .await;
+        assert_eq!(result.exit_code, 0);
+        assert!(result.stdout.contains("2:world"));
+    }
+
+    #[tokio::test]
+    async fn test_rg_no_line_number_flag_short() {
+        // -N flag explicitly disables line numbers
+        let result = run_rg(
+            &["-N", "world", "/test.txt"],
+            None,
+            &[("/test.txt", b"hello\nworld\n")],
+        )
+        .await;
+        assert_eq!(result.exit_code, 0);
+        assert_eq!(result.stdout.trim(), "world");
+    }
+
+    #[tokio::test]
+    async fn test_rg_no_line_number_flag_long() {
+        // --no-line-number flag explicitly disables line numbers
+        let result = run_rg(
+            &["--no-line-number", "world", "/test.txt"],
+            None,
+            &[("/test.txt", b"hello\nworld\n")],
+        )
+        .await;
+        assert_eq!(result.exit_code, 0);
+        assert_eq!(result.stdout.trim(), "world");
+    }
+
+    #[tokio::test]
+    async fn test_rg_line_number_long_flag() {
+        // --line-number flag enables line numbers
+        let result = run_rg(
+            &["--line-number", "world", "/test.txt"],
+            None,
+            &[("/test.txt", b"hello\nworld\n")],
+        )
+        .await;
+        assert_eq!(result.exit_code, 0);
+        assert!(result.stdout.contains("2:world"));
+    }
+
+    #[tokio::test]
+    async fn test_rg_stdin_no_line_numbers() {
+        // Stdin piped: no line numbers by default
+        let result = run_rg(&["hello"], Some("hello world\n"), &[]).await;
+        assert_eq!(result.exit_code, 0);
+        assert_eq!(result.stdout.trim(), "hello world");
+        assert!(!result.stdout.contains("1:"));
     }
 }
diff --git a/crates/bashkit/tests/spec_cases/grep/rg.test.sh b/crates/bashkit/tests/spec_cases/grep/rg.test.sh
new file mode 100644
index 00000000..f9172947
--- /dev/null
+++ b/crates/bashkit/tests/spec_cases/grep/rg.test.sh
@@ -0,0 +1,94 @@
+### rg_basic_match
+# Basic rg pattern match
+printf 'hello world\ngoodbye\nhello again\n' | rg hello
+### expect
+hello world
+hello again
+### end
+
+### rg_no_line_numbers_default
+# rg suppresses line numbers when piped (non-tty)
+printf 'foo\nbar\nbaz\n' | rg bar
+### expect
+bar
+### end
+
+### rg_line_numbers_with_n
+# -n flag enables line numbers
+printf 'foo\nbar\nbaz\n' | rg -n bar
+### expect
+2:bar
+### end
+
+### rg_no_line_number_N_flag
+# -N flag explicitly suppresses line numbers
+printf 'foo\nbar\n' | rg -N bar
+### expect
+bar
+### end
+
+### rg_no_line_number_long
+# --no-line-number long flag
+printf 'foo\nbar\n' | rg --no-line-number bar
+### expect
+bar
+### end
+
+### rg_line_number_long
+# --line-number long flag enables line numbers
+printf 'foo\nbar\nbaz\n' | rg --line-number bar
+### expect
+2:bar
+### end
+
+### rg_no_match
+# No match returns exit code 1
+printf 'foo\nbar\n' | rg xyz
+### exit_code: 1
+### expect
+### end
+
+### rg_case_insensitive
+# Case insensitive search
+printf 'Hello\nWORLD\nhello\n' | rg -i hello
+### expect
+Hello
+hello
+### end
+
+### rg_count
+# Count matches
+printf 'foo\nbar\nfoo again\n' | rg -c foo
+### expect
+2
+### end
+
+### rg_invert_match
+# Invert match
+printf 'foo\nbar\nbaz\n' | rg -v foo
+### expect
+bar
+baz
+### end
+
+### rg_fixed_strings
+# Fixed string (no regex)
+printf 'a.b\naxb\n' | rg -F 'a.b'
+### expect
+a.b
+### end
+
+### rg_word_boundary
+# Word boundary match
+printf 'cat\ncatch\nmy cat\n' | rg -w cat
+### expect
+cat
+my cat
+### end
+
+### rg_max_count
+# Stop after N matches
+printf 'foo\nfoo\nfoo\n' | rg -m 1 foo
+### expect
+foo
+### end