
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
Given an ellipse $\dfrac{x^2}{a^2} + \dfrac{y^2}{b^2} = 1 (a > b > 0)$, where the left vertex is $A$, the top vertex is $B$, and the right focus is $F$. Let the midpoint of segment $AB$ be $M$. If $2\overrightarrow{MA} \cdot \overrightarrow{MF} + |\overrightarrow{BF}|^2 \geqslant 0$, then the range of the eccentricity of the ellipse is \_\_\_\_\_\_\_\_\_\_\_\_\_\_\_.

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