It is generally neutral but could be positive or negative, depending on context and who makes the judgement. Any time you describe someone with a single adjective you run the danger of sounding accusatory. For example, if you say someone is "talkative" it might sound a bit insulting even though there is nothing wrong with being talkative. To make an adjective sound better, soften it up a bit: She does know how to flirt. She has perfected the art of flirtation. She can be flirtatious now and then. I enjoy watching her flirt. She is a natural.

Generally speaking ‘flirtatious’ is pejorative i e. negative. It implies that the person is trying to attract attention by being sexually suggestive. However, as so often, context will determine the connotation, and in some situations it will be seen as ‘coquettish’ - appealing and attractive.

Hi Sara Being a flirt can be both good and bad. 1. In a romantic scenario... it is just fine, perhaps even the normal way to behave. 2. In a professional setting or work environment, it may be seen as bad especially if it interferes with work. In general being a flirt or being flirtatious means being charming in a way that is suggests romance. So it depends on the situation.