diff --git a/src/cortex-cli/src/agent_cmd/tests.rs b/src/cortex-cli/src/agent_cmd/tests.rs
index e2ff07f9..18f7ba75 100644
--- a/src/cortex-cli/src/agent_cmd/tests.rs
+++ b/src/cortex-cli/src/agent_cmd/tests.rs
@@ -3,10 +3,9 @@
 #[cfg(test)]
 mod tests {
     use crate::agent_cmd::cli::{CopyArgs, ExportArgs};
-    use crate::agent_cmd::loader::{
-        load_builtin_agents, parse_frontmatter, read_file_with_encoding,
-    };
+    use crate::agent_cmd::loader::{load_builtin_agents, parse_frontmatter};
     use crate::agent_cmd::types::AgentMode;
+    use crate::utils::file::read_file_with_encoding;
 
     #[test]
     fn test_read_file_with_utf8() {
diff --git a/src/cortex-cli/src/github_cmd.rs b/src/cortex-cli/src/github_cmd.rs
index 83763b3b..fedd86f6 100644
--- a/src/cortex-cli/src/github_cmd.rs
+++ b/src/cortex-cli/src/github_cmd.rs
@@ -410,21 +410,7 @@ async fn handle_issue_comment(
     client.add_reaction(comment.comment_id, "eyes").await?;
 
     // Process the command
-    let response = match command.as_str() {
-        "help" => get_help_message(),
-        "review" => {
-            if comment.is_pull_request {
-                "Starting code review... (not yet implemented)".to_string()
-            } else {
-                "This command is only available on pull requests.".to_string()
-            }
-        }
-        "fix" => "Analyzing and suggesting fixes... (not yet implemented)".to_string(),
-        _ => format!(
-            "Unknown command: `{}`\n\nUse `/cortex help` to see available commands.",
-            command
-        ),
-    };
+    let response = build_cortex_command_response(&command, comment.is_pull_request);
 
     // Post response comment
     client
@@ -439,6 +425,26 @@ async fn handle_issue_comment(
     Ok(())
 }
 
+fn build_cortex_command_response(command: &str, is_pull_request: bool) -> String {
+    match command {
+        "help" => get_help_message(),
+        "review" => {
+            if is_pull_request {
+                "Starting code review... (not yet implemented)".to_string()
+            } else {
+                "This command is only available on pull requests.".to_string()
+            }
+        }
+        "fix" => "Analyzing and suggesting fixes... (not yet implemented)".to_string(),
+        "explain" => "Explaining code changes... (not yet implemented)".to_string(),
+        "test" => "Suggesting tests for changes... (not yet implemented)".to_string(),
+        _ => format!(
+            "Unknown command: `{}`\n\nUse `/cortex help` to see available commands.",
+            command
+        ),
+    }
+}
+
 /// Handle pull request events.
 async fn handle_pull_request(
     token: &str,
@@ -845,6 +851,21 @@ mod tests {
         let help = get_help_message();
         assert!(help.contains("/cortex help"));
         assert!(help.contains("/cortex review"));
+        assert!(help.contains("/cortex explain"));
+        assert!(help.contains("/cortex test"));
+    }
+
+    #[test]
+    fn test_advertised_commands_have_responses() {
+        for command in ["explain", "test"] {
+            let response = build_cortex_command_response(command, true);
+
+            assert!(
+                !response.contains("Unknown command"),
+                "{command} should not return unknown-command help"
+            );
+            assert!(response.contains("not yet implemented"));
+        }
     }
 
     #[tokio::test]