Cotter not happy with 'mixed bag'
This caution came despite his team ending an eight-month wait for a win, with a bruising 16-12 victory over Italy.
In perfect conditions in Turin the Scots turned the match around in the final 10 minutes, when Henry Pyrgos scored the game's only try with Duncan Weir kicking the conversion to finish on 11 points.
Scotland host Italy at Murrayfield next week and face France in Paris on September 5 in what will be their final Test before the game's showpiece event in England next month.
Although Cotter welcomed the win against a very "physical" Italy side, he admitted it was a "mixed bag of positives and negatives".
"It's only our second game as we build up for the World Cup, but we showed strength of character which played a part in this win and we withstood a lot of Italian attacks," Cotter said.
"It was a hard game and anything but simple but we made it hard for ourselves. But then we found a way to win and that's important.
"Italy are a tough team and are very physical. It was a mixed bag of positives and negatives and we have a lot of thinking to do and plenty to work on."
After a 22-28 defeat to Ireland in Dublin last week, Cotter made 11 changes in a bid to run the rule over most of his squad.
He had initially handed the captain's armband to Grant Gilchrist 10 months after injury cost the big Edinburgh lock the captaincy ahead of last year's year-end internationals.
Yet Gilchrist suffered another blow when he was ruled out of the game with illness, meaning Alasdair Strokosch – who did not play against Ireland – skippered the visitors.
With Italy's iconic captain Sergio Parisse sidelined with illness, Fiji-born Samuela Vunisa stepped into the No.8 position with Quintin Geldenhuys taking the captain's armband for the Azzurri.
"Leading the team out was a big honour for me," said Geldenhuys.
It was Italy's first official game since a poor showing in the Six Nations and coach Jacques Brunel's squad choice was determined by a combination of injury, illness and suspension.
Former Scotland Under-20 flyhalf Tommaso Allan, rarely used in the Six Nations, was solid in the absence of New Zealand-born Kelly Haimona, who is ruled out of the tournament with injury.
Outside centre Tommaso Benvenuti was handed his first start in two years while Guglielmo Palazzani came in at scrumhalf to replace suspended Edoardo Gori.
Despite the perfect conditions, it was a scrappy, nervous affair that only rarely showed either side's attacking flair.
Scotland raced to a 6-0 lead thanks to a pair of early Weir penalties as Italy paid the price for indiscipline, although Allan brought Italy level at 9-9 on the stroke of half-time.
Italy came agonisingly close to the opening try 10 minutes after the restart when prop Martin Castrogiovanni was held up with ball in hand after crossing the tryline.
The hosts then pulled in front thanks to a 40-metre Allan penalty.
But after both sides made a series of changes, Scotland came close to the opening try when Peter Horne set off on a mazy run, only to be hauled down inside Italy's 22-metre area by Luke McLean.
Minutes later, Scotland bounced back from a series of handling errors at the halfway line to catch Italy unawares down the right flank with fullback Greg Tonks drawing the last man before offloading to Pyrgos.
"We managed to get a try, but it could have gone either way," Cotter added.
Italy will travel to Edinburgh hoping for a repeat of last February when they stunned Cotter's side 22-19 in the Six Nations.
"It's disappointing to lose a match like this after dominating possession so much," said Brunel.
"But it was our first game and we were up against a Scotland side that could have beaten Ireland last week."
In front of a home crowd, Cotter said he will be expecting a more constructive approach.
"Life is easier when you are winning games but we know we'll have to lift our performance," he added.
"We've got to be honest about it and look to construct a game next week."
Agence France-Presse
