Corollary 8.5.4.19. Let $\operatorname{\mathcal{C}}$ be an $\infty $-category which is sequentially complete (or sequentially cocomplete). Then $\operatorname{\mathcal{C}}$ is idempotent-complete.
$\Newextarrow{\xhookrightarrow}{10,10}{0x21AA}$
Proof. It follows from Proposition 8.5.4.18 (and Corollary 7.2.2.12) that the $\infty $-category $\operatorname{\mathcal{C}}$ admits limits (or colimits) indexed by the $\infty $-category $\operatorname{N}_{\bullet }( \operatorname{Idem})$, and is therefore idempotent-complete by virtue of Proposition 8.5.4.10. $\square$