ss="operator">:</span> <span class="builtin">string</span><span class="punctuation">)</span><span class="operator">:</span> <span class="type"><a href="/api/checkpoints/interfaces/checkpoints/checkpoints/">Checkpoints</a></span> <span class="operator">|</span> <span class="keyword">undefined</span></code></pre><div class="table"><table><tr><th></th><th>Type</th><th>Description</th></tr><tr><th><code>id<span class="operator">?</span></code></th><td><code><span class="builtin">string</span></code></td><td><p>