community[minor]: Add puppeteer agent tool

libs/langchain-community/.gitignore

@@ -78,6 +78,10 @@ tools/ifttt.cjs
 tools/ifttt.js
 tools/ifttt.d.ts
 tools/ifttt.d.cts
+tools/puppeteer.cjs
+tools/puppeteer.js
+tools/puppeteer.d.ts
+tools/puppeteer.d.cts
 tools/searchapi.cjs
 tools/searchapi.js
 tools/searchapi.d.ts

libs/langchain-community/langchain.config.js

@@ -51,6 +51,7 @@ export const config = {
     "tools/google_places": "tools/google_places",
     "tools/google_routes": "tools/google_routes",
     "tools/ifttt": "tools/ifttt",
+    "tools/puppeteer": "tools/puppeteer",
     "tools/searchapi": "tools/searchapi",
     "tools/searxng_search": "tools/searxng_search",
     "tools/serpapi": "tools/serpapi",
@@ -324,6 +325,7 @@ export const config = {
     "tools/discord",
     "tools/gmail",
     "tools/google_calendar",
+    "tools/puppeteer",
     "agents/toolkits/aws_sfn",
     "callbacks/handlers/llmonitor",
     "callbacks/handlers/lunary",

libs/langchain-community/package.json

@@ -880,6 +880,15 @@
       "import": "./tools/ifttt.js",
       "require": "./tools/ifttt.cjs"
     },
+    "./tools/puppeteer": {
+      "types": {
+        "import": "./tools/puppeteer.d.ts",
+        "require": "./tools/puppeteer.d.cts",
+        "default": "./tools/puppeteer.d.ts"
+      },
+      "import": "./tools/puppeteer.js",
+      "require": "./tools/puppeteer.cjs"
+    },
     "./tools/searchapi": {
       "types": {
         "import": "./tools/searchapi.d.ts",
@@ -3097,6 +3106,10 @@
     "tools/ifttt.js",
     "tools/ifttt.d.ts",
     "tools/ifttt.d.cts",
+    "tools/puppeteer.cjs",
+    "tools/puppeteer.js",
+    "tools/puppeteer.d.ts",
+    "tools/puppeteer.d.cts",
     "tools/searchapi.cjs",
     "tools/searchapi.js",
     "tools/searchapi.d.ts",

libs/langchain-community/src/load/import_constants.ts

@@ -7,6 +7,7 @@ export const optionalImportEntrypoints: string[] = [
   "langchain_community/tools/discord",
   "langchain_community/tools/gmail",
   "langchain_community/tools/google_calendar",
+  "langchain_community/tools/puppeteer",
   "langchain_community/agents/toolkits/aws_sfn",
   "langchain_community/embeddings/bedrock",
   "langchain_community/embeddings/cloudflare_workersai",

libs/langchain-community/src/tools/puppeteer.ts

@@ -0,0 +1,181 @@
+import { launch } from "puppeteer";
+import { load } from "cheerio";
+
+import type { LanguageModelLike } from "@langchain/core/language_models/base";
+import { Tool, ToolParams } from "@langchain/core/tools";
+import { RunnableSequence } from "@langchain/core/runnables";
+import { StringOutputParser } from "@langchain/core/output_parsers";
+import type { EmbeddingsInterface } from "@langchain/core/embeddings";
+
+import {
+  RecursiveCharacterTextSplitter,
+  TextSplitter,
+} from "@langchain/textsplitters";
+
+import { MemoryVectorStore } from "langchain/vectorstores/memory";
+import { formatDocumentsAsString } from "langchain/util/document";
+import { Document } from "langchain/document";
+
+export const parseInputs = (inputs: string): [string, string] => {
+  const [baseUrl, task] = inputs.split(",").map((input) => {
+    let t = input.trim();
+    t = t.startsWith('"') ? t.slice(1) : t;
+    t = t.endsWith('"') ? t.slice(0, -1) : t;
+    t = t.endsWith("/") ? t.slice(0, -1) : t;
+    return t.trim();
+  });
+
+  return [baseUrl, task];
+};
+
+export const getRelevantHtml = async (html: string): Promise<string> => {
+  const $ = load(html);
+
+  const tagsToRemove = ["script", "svg", "style"];
+
+  for (const tag of tagsToRemove) {
+    await $(tag).remove();
+  }
+
+  return $("body").html()?.trim().replace(/\n+/g, " ") ?? "";
+};
+
+export const getHtml = async (
+  baseUrl: string,
+  headers: Headers = DEFAULT_HEADERS
+) => {
+  const browser = await launch({
+    args: ["--no-sandbox", "--disable-setuid-sandbox"],
+    ignoreDefaultArgs: ["--disable-extensions"],
+  });
+
+  const page = await browser.newPage();
+
+  await page.setExtraHTTPHeaders(headers);
+  await page.goto(baseUrl, { waitUntil: "networkidle0" });
+
+  const bodyHtml = await page.content();
+  await browser.close();
+
+  return bodyHtml;
+};
+
+const DEFAULT_HEADERS = {
+  Accept:
+    "text/html,application/xhtml+xml,application/xml;q=0.9,image/avif,image/webp,*/*;q=0.8",
+  "Accept-Encoding": "gzip, deflate",
+  "Accept-Language": "en-US,en;q=0.5",
+
+  Referer: "https://www.google.com/",
+  "Sec-Fetch-Dest": "document",
+  "Sec-Fetch-Mode": "navigate",
+  "Sec-Fetch-Site": "cross-site",
+  "Upgrade-Insecure-Requests": "1",
+  "User-Agent":
+    "Mozilla/5.0 (X11; Ubuntu; Linux x86_64; rv:109.0) Gecko/20100101 Firefox/111.0",
+};
+
+// eslint-disable-next-line @typescript-eslint/no-explicit-any
+type Headers = Record<string, any>;
+
+/**
+ * Defines the arguments that can be passed to the WebBrowser constructor.
+ * It extends the ToolParams interface and includes properties for a
+ * language model, embeddings, HTTP headers, and a text splitter.
+ */
+export interface PuppeteerBrowserArgs extends ToolParams {
+  model: LanguageModelLike;
+
+  embeddings: EmbeddingsInterface;
+
+  headers?: Headers;
+
+  textSplitter?: TextSplitter;
+}
+
+export class PuppeteerBrowser extends Tool {
+  name = "puppeteer-browser";
+
+  description = `Useful for when you need to find something on a webpage. Input should be a comma separated list of "ONE valid URL including protocol","What you want to find on the page or empty string for a summary"`;
+
+  static lc_name() {
+    return "PuppeteerBrowser";
+  }
+
+  get lc_namespace() {
+    return [...super.lc_namespace, "puppeteer"];
+  }
+
+  private model: LanguageModelLike;
+
+  private embeddings: EmbeddingsInterface;
+
+  private headers: Headers;
+
+  private textSplitter: TextSplitter;
+
+  constructor({
+    model,
+    headers,
+    embeddings,
+    textSplitter,
+  }: PuppeteerBrowserArgs) {
+    super(...arguments);
+
+    this.model = model;
+    this.embeddings = embeddings;
+    this.headers = headers ?? DEFAULT_HEADERS;
+
+    this.textSplitter =
+      textSplitter ??
+      new RecursiveCharacterTextSplitter({
+        chunkSize: 2000,
+        chunkOverlap: 200,
+      });
+  }
+
+  async _call(inputs: string) {
+    const [baseUrl, task] = parseInputs(inputs);
+    const doSummary = !task;
+
+    let text;
+    try {
+      const html = await getHtml(baseUrl, this.headers);
+      text = await getRelevantHtml(html);
+    } catch (e) {
+      if (e) {
+        return e.toString();
+      }
+      return "There was a problem connecting to the site";
+    }
+
+    const texts = await this.textSplitter.splitText(text);
+
+    let context;
+    if (doSummary) {
+      context = texts.slice(0, 4).join("\n");
+    } else {
+      const docs = texts.map(
+        (pageContent: string) =>
+          new Document({
+            pageContent,
+            metadata: [],
+          })
+      );
+
+      const vectorStore = await MemoryVectorStore.fromDocuments(
+        docs,
+        this.embeddings
+      );
+      const results = await vectorStore.similaritySearch(task, 4);
+      context = formatDocumentsAsString(results);
+    }
+
+    const input = `Text:${context}\n\nI need ${
+      doSummary ? "a summary" : task
+    } from the above text, also provide up to 5 markdown links from within that would be of interest (always including URL and text). Links should be provided, if present, in markdown syntax as a list under the heading "Relevant Links:".`;
+
+    const chain = RunnableSequence.from([this.model, new StringOutputParser()]);
+    return chain.invoke(input);
+  }
+}

libs/langchain-community/src/tools/tests/puppeteer.test.ts

@@ -0,0 +1,33 @@
+import { test, expect } from "@jest/globals";
+import { getRelevantHtml, parseInputs } from "../puppeteer.js";
+
+test("getRelevantHtml should extract relevant parts of the html", async () => {
+  const html =
+    "<html><body><div><svg>ahh</svg><strong>Hello,</strong> world!<style>*{background-color: pink;}</style><script>Remove me!</script></div></body>";
+
+  expect(getRelevantHtml(html)).toBe(
+    "<div><strong>Hello,</strong> world!</div>"
+  );
+});
+
+test("parseInputs", () => {
+  expect(parseInputs(`"https://supermagictaste.com",""`)).toEqual([
+    "https://supermagictaste.com",
+    "",
+  ]);
+  expect(
+    parseInputs(`"https://supermagictaste.com","word of the day"`)
+  ).toEqual(["https://supermagictaste.com", "word of the day"]);
+  expect(parseInputs(`"https://supermagictaste.com","`)).toEqual([
+    "https://supermagictaste.com",
+    "",
+  ]);
+  expect(parseInputs(`"https://supermagictaste.com",`)).toEqual([
+    "https://supermagictaste.com",
+    "",
+  ]);
+  expect(parseInputs(`"https://supermagictaste.com"`)).toEqual([
+    "https://supermagictaste.com",
+    undefined,
+  ]);
+});