Find the exact value of $\csc \frac{\pi}{4}$ in simplest form with a rational denominator.

Step 1 ：The cosecant function is defined as the reciprocal of the sine function. Therefore, to find the exact value of \(\csc \frac{\pi}{4}\), we first need to find the value of \(\sin \frac{\pi}{4}\).

Step 2 ：The value of \(\sin \frac{\pi}{4}\) is well-known and is \(\frac{\sqrt{2}}{2}\).

Step 3 ：Therefore, the value of \(\csc \frac{\pi}{4}\) is the reciprocal of \(\frac{\sqrt{2}}{2}\), which is \(\frac{2}{\sqrt{2}}\).

Step 4 ：However, the question asks for the answer in simplest form with a rational denominator. Therefore, we need to rationalize the denominator of \(\frac{2}{\sqrt{2}}\).

Step 5 ：The rationalized expression is \(\sqrt{2}\).

Step 6 ：Final Answer: \(\boxed{\sqrt{2}}\)