feat: Add leading comments (--) detection for 'run_sql_readonly'

Read only queries are no longer flagged as non-readonly when starting
with double dash comments.

include/MySQL_Tool_Handler.h

@@ -285,6 +285,22 @@ public:
 		int timeout_sec = 2
 	);
 
+	/**
+	 * @brief Strip simple SQL comments from the start of a query
+	 *
+	 * Removes leading '-- ' style comments from SQL queries.
+	 * Handles multiple comment lines and whitespace before/after comments.
+	 * This is a simple pre-processing step to allow queries with leading comments.
+	 *
+	 * @param sql The SQL query that may have leading comments
+	 * @return SQL query with leading comments removed
+	 *
+	 * @note Only removes comments from the START of the query
+	 * @note Does not handle inline comments (comments within the query)
+	 * @note Does not handle block comments
+	 */
+	std::string strip_leading_comments(const std::string& sql);
+
 	/**
 	 * @brief Explain a query (EXPLAIN/EXPLAIN ANALYZE)
 	 * @param sql SQL query to explain

include/Query_Tool_Handler.h

@@ -146,6 +146,22 @@ private:
 	 */
 	bool is_dangerous_query(const std::string& query);
 
+	/**
+	 * @brief Strip simple SQL comments from the start of a query
+	 *
+	 * Removes leading '-- ' style comments from SQL queries.
+	 * Handles multiple comment lines and whitespace before/after comments.
+	 * This is a simple pre-processing step to allow queries with leading comments.
+	 *
+	 * @param sql The SQL query that may have leading comments
+	 * @return SQL query with leading comments removed
+	 *
+	 * @note Only removes comments from the START of the query
+	 * @note Does not handle inline comments (comments within the query)
+	 * @note Does not handle block comments
+	 */
+	std::string strip_leading_comments(const std::string& sql);
+
 	// Friend function for tracking tool invocations
 	friend void track_tool_invocation(Query_Tool_Handler*, const std::string&, const std::string&, const std::string&, unsigned long long);
 

lib/MySQL_Tool_Handler.cpp

@@ -1049,6 +1049,52 @@ std::string MySQL_Tool_Handler::sample_distinct(
 	return result.dump();
 }
 
+/**
+ * @brief Strip simple SQL comments from the start of a query
+ *
+ * Removes leading '-- ' style comments from SQL queries.
+ * Handles multiple comment lines and whitespace before/after comments.
+ * This is a simple pre-processing step to allow queries with leading comments.
+ *
+ * @param sql The SQL query that may have leading comments
+ * @return SQL query with leading comments removed
+ *
+ * @note Only removes comments from the START of the query
+ * @note Does not handle inline comments (comments within the query)
+ * @note Does not handle \/\* *\/ style comments
+ */
+std::string MySQL_Tool_Handler::strip_leading_comments(const std::string& sql) {
+	std::string result = sql;
+	size_t pos = 0;
+	size_t len = result.length();
+
+	// Skip any leading whitespace
+	while (pos < len && isspace(result[pos])) {
+		pos++;
+	}
+
+	// Remove leading '-- ' comment lines
+	while (pos < len && result.substr(pos, 3) == "-- ") {
+		// Found a comment, skip to end of line
+		while (pos < len && result[pos] != '\n') {
+			pos++;
+		}
+
+		// Skip the newline
+		if (pos < len && result[pos] == '\n') {
+			pos++;
+		}
+
+		// Skip any leading whitespace before next comment
+		while (pos < len && isspace(result[pos])) {
+			pos++;
+		}
+	}
+
+	// Return the query without leading comments
+	return result.substr(pos);
+}
+
 std::string MySQL_Tool_Handler::run_sql_readonly(
 	const std::string& sql,
 	int max_rows,
@@ -1057,14 +1103,16 @@ std::string MySQL_Tool_Handler::run_sql_readonly(
 	json result;
 	result["success"] = false;
 
+	// Strip leading comments from the query
+	std::string query = strip_leading_comments(sql);
+
 	// Validate query is read-only
-	if (!validate_readonly_query(sql)) {
+	if (!validate_readonly_query(query)) {
 		result["error"] = "Query validation failed: not SELECT-only or contains dangerous keywords";
 		return result.dump();
 	}
 
 	// Add LIMIT if not present and not an aggregate query
-	std::string query = sql;
 	std::string upper = sql;
 	std::transform(upper.begin(), upper.end(), upper.begin(), ::toupper);
 

lib/Query_Tool_Handler.cpp

@@ -610,6 +610,35 @@ bool Query_Tool_Handler::is_dangerous_query(const std::string& query) {
 	return false;
 }
 
+std::string Query_Tool_Handler::strip_leading_comments(const std::string& sql) {
+	std::string result = sql;
+	size_t pos = 0;
+	size_t len = result.length();
+
+	// Skip leading whitespace
+	while (pos < len && isspace(result[pos])) {
+		pos++;
+	}
+
+	// Remove leading '-- ' comment lines
+	while (pos < len && result.substr(pos, 2) == "--") {
+		// Skip until end of line
+		while (pos < len && result[pos] != '\n') {
+			pos++;
+		}
+		// Skip the newline
+		if (pos < len && result[pos] == '\n') {
+			pos++;
+		}
+		// Skip leading whitespace after the comment
+		while (pos < len && isspace(result[pos])) {
+			pos++;
+		}
+	}
+
+	return result.substr(pos);
+}
+
 json Query_Tool_Handler::create_tool_schema(
 	const std::string& tool_name,
 	const std::string& description,
@@ -1749,6 +1778,9 @@ json Query_Tool_Handler::execute_tool(const std::string& tool_name, const json&
 
 			delete qpo;
 
+			// Strip leading comments from query
+			sql = strip_leading_comments(sql);
+
 			// Continue with validation and execution
 			if (!validate_readonly_query(sql)) {
 				result = create_error_response("SQL is not read-only");