<|system|>
Compute $\arctan \left( -\frac{1}{\sqrt{3}} \right).$  Express your answer in radians.</s>.
<|user|>
Can you answer based on context?
<|assistant|>
Since $\tan \left( -\frac{\pi}{6} \right) = -\frac{1}{\sqrt{3}},$ $\arctan \left( -\frac{1}{\sqrt{3}} \right) = -\frac{\pi}{6}.$