LangChain

npm install langchain @langchain/anthropic zod

// socialcrawl-langchain.ts
// Run with: SOCIALCRAWL_API_KEY=sc_... ANTHROPIC_API_KEY=... npx tsx socialcrawl-langchain.ts
import { createAgent, tool } from "langchain";
import * as z from "zod";

const API_KEY = process.env.SOCIALCRAWL_API_KEY;
if (!API_KEY) throw new Error("Set SOCIALCRAWL_API_KEY");

const socialcrawl = tool(
  async ({ platform, resource, params }) => {
    const url = new URL(
      `https://www.socialcrawl.dev/v1/${platform}/${resource}`,
    );
    for (const [key, value] of Object.entries(params ?? {})) {
      url.searchParams.set(key, String(value));
    }
    const res = await fetch(url, { headers: { "x-api-key": API_KEY } });
    const json = await res.json();
    if (!json.success) {
      // Hand the model a directive it can act on, not a raw error envelope.
      return `SocialCrawl error ${json.error.type}: ${json.error.message}. See ${json.error.doc_url}`;
    }
    // Return a string so the model can read it back as a tool message.
    return JSON.stringify(json.data);
  },
  {
    name: "socialcrawl",
    description:
      "Fetch current public social media, commerce, and review data from SocialCrawl; documented endpoint caches apply. " +
      "Covers TikTok, Instagram, YouTube, LinkedIn, Reddit, Amazon and more. " +
      "Set `platform` (e.g. 'tiktok'), `resource` (e.g. 'profile'), and `params` " +
      "(the endpoint's query fields, e.g. { handle: 'charlidamelio' }).",
    schema: z.object({
      platform: z
        .string()
        .describe("Platform slug, e.g. 'tiktok' or 'youtube'"),
      resource: z
        .string()
        .describe("Endpoint resource, e.g. 'profile' or 'search'"),
      params: z
        .record(z.string(), z.union([z.string(), z.number()]))
        .describe("Query parameters for the endpoint"),
    }),
  },
);

const agent = createAgent({
  model: "claude-sonnet-5",
  tools: [socialcrawl],
});

const result = await agent.invoke({
  messages: [
    {
      role: "user",
      content: "How many followers does @charlidamelio have on TikTok?",
    },
  ],
});

console.log(result.messages.at(-1)?.content);