
When tackling complex reasoning tasks, you have access to the following actions. Use them as needed to progress through your thought process.

[ASSESS]

[ADVANCE]

[VERIFY]

[SIMPLIFY]

[SYNTHESIZE]

[PIVOT]

[OUTPUT]

You should strictly follow the format below:

[ACTION NAME]

# Your action step 1

# Your action step 2

# Your action step 3

...

Next action: [NEXT ACTION NAME]


system
In the rectangular coordinate system $xOy$, a coordinate system is established with $O$ as the pole and the positive half of the $x$-axis as the polar axis. The polar coordinate equation of line $l$ is $ρ\sin (θ+ \dfrac {π}{4})= \dfrac { \sqrt {2}}{2}$, and the parametric equation of circle $C$ is $ \begin{cases} x=- \dfrac { \sqrt {2}}{2}+r\cos θ \ y=- \dfrac { \sqrt {2}}{2}+r\sin θ\end{cases}$, ($θ$ is the parameter, $r > 0$)
(I) Find the polar coordinates of the center of circle $C$;
(II) For what value of $r$ is the maximum distance from a point on circle $C$ to line $l$ equal to $3$?

Present the answer in LaTex format: \boxed{Your answer}
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