To calculate $(-1)^{2024}-\frac{1}{2} \times [8-(-2)^{2}]$, we follow these steps:

1. Evaluate $(-1)^{2024}$: Since any even power of $-1$ is $1$, we have $(-1)^{2024} = 1$.
2. Evaluate $(-2)^{2}$: Squaring $-2$ gives $(-2)^{2} = 4$.
3. Substitute and simplify inside the brackets: $8-(-2)^{2} = 8-4 = 4$.
4. Multiply by $\frac{1}{2}$: $\frac{1}{2} \times 4 = 2$.
5. Subtract from the first part: $1 - 2 = -1$.

Putting it all together in a detailed step-by-step calculation:

$$\begin{align*} (-1)^{2024}-\frac{1}{2} \times [8-(-2)^{2}] & = 1-\frac{1}{2} \times \left(8-4\right) \\ & = 1-\frac{1}{2} \times 4 \\ & = 1-2 \\ & = -1. \end{align*}$$

Therefore, the final answer is $\boxed{-1}$.