Get the bluesky first posts.

first.js

import bsky from "@atproto/api";
const { BskyAgent } = bsky;
const agent = new BskyAgent({ service: "https://bsky.social" });
const { data } = await agent.api.com.atproto.repo.listRecords({
  reverse: true,
  repo: "shino3.bsky.social",
  collection: "app.bsky.feed.post",
});
console.log(data.records.slice(-1)[0]);