Remark 89.23.3. Let $(\underline{R_0}, \underline{R_1}, s, t, c)|_{\mathcal{C}_\Lambda }$ be a prorepresentable groupoid in functors on $\mathcal{C}_\Lambda$. Then $(\underline{R_0}, \underline{R_1}, s, t, c)|_{\mathcal{C}_\Lambda }$ is smooth if and only if $R_1$ is a power series over $R_0$ via both $s$ and $t$. This follows from Lemma 89.8.6.

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