Update some Tools Docs (#3913)

Haven't gotten to all of them, but this:
- Updates some of the tools notebooks to actually instantiate a tool
(many just show a 'utility' rather than a tool. More changes to come in
separate PR)
- Move the `Tool` and decorator definitions to `langchain/tools/base.py`
(but still export from `langchain.agents`)
- Add scene explain to the load_tools() function
- Add unit tests for public apis for the langchain.tools and langchain.agents modules

docs/modules/agents/tools/examples/google_search.ipynb

@@ -33,7 +33,16 @@
    "metadata": {},
    "outputs": [],
    "source": [
-    "from langchain.utilities import GoogleSearchAPIWrapper"
+    "from langchain.tools import Tool\n",
+    "from langchain.utilities import GoogleSearchAPIWrapper\n",
+    "\n",
+    "search = GoogleSearchAPIWrapper()\n",
+    "\n",
+    "tool = Tool(\n",
+    "    name = \"Google Search\",\n",
+    "    description=\"Search Google for recent results.\",\n",
+    "    func=search.run\n",
+    ")"
    ]
   },
   {
@@ -41,30 +50,20 @@
    "execution_count": 3,
    "id": "84b8f773",
    "metadata": {},
-   "outputs": [],
-   "source": [
-    "search = GoogleSearchAPIWrapper()"
-   ]
-  },
-  {
-   "cell_type": "code",
-   "execution_count": 4,
-   "id": "068991a6",
-   "metadata": {},
    "outputs": [
     {
      "data": {
       "text/plain": [
-       "'1 Child\\'s First Name. 2. 6. 7d. Street Address. 71. (Type or print). BARACK. Sex. 3. This Birth. 4. If Twin or Triplet,. Was Child Born. Barack Hussein Obama II is an American retired politician who served as the 44th president of the United States from 2009 to 2017. His full name is Barack Hussein Obama II. Since the “II” is simply because he was named for his father, his last name is Obama. Feb 9, 2015 ... Michael Jordan misspelled Barack Obama\\'s first name on 50th-birthday gift ... Knowing Obama is a Chicagoan and huge basketball fan,\\xa0... Aug 18, 2017 ... It took him several seconds and multiple clues to remember former President Barack Obama\\'s first name. Miller knew that every answer had to end\\xa0... First Lady Michelle LaVaughn Robinson Obama is a lawyer, writer, and the wife of the 44th President, Barack Obama. She is the first African-American First\\xa0... Barack Obama, in full Barack Hussein Obama II, (born August 4, 1961, Honolulu, Hawaii, U.S.), 44th president of the United States (2009–17) and the first\\xa0... When Barack Obama was elected president in 2008, he became the first African American to hold ... The Middle East remained a key foreign policy challenge. Feb 27, 2020 ... President Barack Obama was born Barack Hussein Obama, II, as shown here on his birth certificate here . As reported by Reuters here , his\\xa0... Jan 16, 2007 ... 4, 1961, in Honolulu. His first name means \"one who is blessed\" in Swahili. While Obama\\'s father, Barack Hussein Obama Sr., was from Kenya, his\\xa0...'"
+       "\"STATE OF HAWAII. 1 Child's First Name. (Type or print). 2. Sex. BARACK. 3. This Birth. CERTIFICATE OF LIVE BIRTH. FILE. NUMBER 151 le. lb. Middle Name. Barack Hussein Obama II is an American former politician who served as the 44th president of the United States from 2009 to 2017. A member of the Democratic\\xa0... When Barack Obama was elected president in 2008, he became the first African American to hold ... The Middle East remained a key foreign policy challenge. Jan 19, 2017 ... Jordan Barack Treasure, New York City, born in 2008 ... Jordan Barack Treasure made national news when he was the focus of a New York newspaper\\xa0... Portrait of George Washington, the 1st President of the United States ... Portrait of Barack Obama, the 44th President of the United States\\xa0... His full name is Barack Hussein Obama II. Since the “II” is simply because he was named for his father, his last name is Obama. Mar 22, 2008 ... Barry Obama decided that he didn't like his nickname. A few of his friends at Occidental College had already begun to call him Barack (his\\xa0... Aug 18, 2017 ... It took him several seconds and multiple clues to remember former President Barack Obama's first name. Miller knew that every answer had to\\xa0... Feb 9, 2015 ... Michael Jordan misspelled Barack Obama's first name on 50th-birthday gift ... Knowing Obama is a Chicagoan and huge basketball fan,\\xa0... 4 days ago ... Barack Obama, in full Barack Hussein Obama II, (born August 4, 1961, Honolulu, Hawaii, U.S.), 44th president of the United States (2009–17) and\\xa0...\""
       ]
      },
-     "execution_count": 4,
+     "execution_count": 3,
      "metadata": {},
      "output_type": "execute_result"
     }
    ],
    "source": [
-    "search.run(\"Obama's first name?\")"
+    "tool.run(\"Obama's first name?\")"
    ]
   },
   {
@@ -78,17 +77,23 @@
   },
   {
    "cell_type": "code",
-   "execution_count": 5,
+   "execution_count": 4,
    "id": "5083fbdd",
    "metadata": {},
    "outputs": [],
    "source": [
-    "search = GoogleSearchAPIWrapper(k=1)"
+    "search = GoogleSearchAPIWrapper(k=1)\n",
+    "\n",
+    "tool = Tool(\n",
+    "    name = \"I'm Feeling Lucky\",\n",
+    "    description=\"Search Google and return the first result.\",\n",
+    "    func=search.run\n",
+    ")"
    ]
   },
   {
    "cell_type": "code",
-   "execution_count": 6,
+   "execution_count": 5,
    "id": "77aaa857",
    "metadata": {},
    "outputs": [
@@ -98,13 +103,13 @@
        "'The official home of the Python Programming Language.'"
       ]
      },
-     "execution_count": 6,
+     "execution_count": 5,
      "metadata": {},
      "output_type": "execute_result"
     }
    ],
    "source": [
-    "search.run(\"python\")"
+    "tool.run(\"python\")"
    ]
   },
   {
@@ -137,48 +142,30 @@
   },
   {
    "cell_type": "code",
-   "execution_count": 7,
+   "execution_count": 6,
    "id": "028f4cba",
    "metadata": {},
    "outputs": [],
    "source": [
-    "search = GoogleSearchAPIWrapper()"
+    "search = GoogleSearchAPIWrapper()\n",
+    "\n",
+    "def top5_results(query):\n",
+    "    return search.results(query, 5)\n",
+    "\n",
+    "tool = Tool(\n",
+    "    name = \"Google Search Snippets\",\n",
+    "    description=\"Search Google for recent results.\",\n",
+    "    func=top5_results\n",
+    ")"
    ]
   },
   {
    "cell_type": "code",
-   "execution_count": 8,
-   "id": "4d8f734f",
+   "execution_count": null,
+   "id": "4d7f92e1",
    "metadata": {},
-   "outputs": [
-    {
-     "data": {
-      "text/plain": [
-       "[{'snippet': 'Discover the innovative world of Apple and shop everything iPhone, iPad, Apple Watch, Mac, and Apple TV, plus explore accessories, entertainment,\\xa0...',\n",
-       "  'title': 'Apple',\n",
-       "  'link': 'https://www.apple.com/'},\n",
-       " {'snippet': \"Jul 10, 2022 ... Whether or not you're up on your apple trivia, no doubt you know how delicious this popular fruit is, and how nutritious. Apples are rich in\\xa0...\",\n",
-       "  'title': '25 Types of Apples and What to Make With Them - Parade ...',\n",
-       "  'link': 'https://parade.com/1330308/bethlipton/types-of-apples/'},\n",
-       " {'snippet': 'An apple is an edible fruit produced by an apple tree (Malus domestica). Apple trees are cultivated worldwide and are the most widely grown species in the\\xa0...',\n",
-       "  'title': 'Apple - Wikipedia',\n",
-       "  'link': 'https://en.wikipedia.org/wiki/Apple'},\n",
-       " {'snippet': 'Apples are a popular fruit. They contain antioxidants, vitamins, dietary fiber, and a range of other nutrients. Due to their varied nutrient content,\\xa0...',\n",
-       "  'title': 'Apples: Benefits, nutrition, and tips',\n",
-       "  'link': 'https://www.medicalnewstoday.com/articles/267290'},\n",
-       " {'snippet': \"An apple is a crunchy, bright-colored fruit, one of the most popular in the United States. You've probably heard the age-old saying, “An apple a day keeps\\xa0...\",\n",
-       "  'title': 'Apples: Nutrition & Health Benefits',\n",
-       "  'link': 'https://www.webmd.com/food-recipes/benefits-apples'}]"
-      ]
-     },
-     "execution_count": 8,
-     "metadata": {},
-     "output_type": "execute_result"
-    }
-   ],
-   "source": [
-    "search.results(\"apples\", 5)"
-   ]
+   "outputs": [],
+   "source": []
   }
  ],
  "metadata": {
@@ -197,7 +184,7 @@
    "name": "python",
    "nbconvert_exporter": "python",
    "pygments_lexer": "ipython3",
-   "version": "3.10.9"
+   "version": "3.11.2"
   },
   "vscode": {
    "interpreter": {

docs/modules/agents/tools/examples/sceneXplain.ipynb

@@ -20,10 +20,37 @@
    "outputs": [],
    "source": [
     "import os\n",
+    "os.environ[\"SCENEX_API_KEY\"] = \"<YOUR_API_KEY>\""
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 2,
+   "metadata": {},
+   "outputs": [],
+   "source": [
+    "from langchain.agents import load_tools\n",
+    "\n",
+    "tools = load_tools([\"sceneXplain\"])"
+   ]
+  },
+  {
+   "attachments": {},
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "Or directly instantiate the tool."
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 1,
+   "metadata": {},
+   "outputs": [],
+   "source": [
     "from langchain.tools import SceneXplainTool\n",
     "\n",
     "\n",
-    "os.environ[\"SCENEX_API_KEY\"] = \"<YOUR_API_KEY>\"\n",
     "tool = SceneXplainTool()\n"
    ]
   },
@@ -73,10 +100,6 @@
     "\n",
     "llm = OpenAI(temperature=0)\n",
     "memory = ConversationBufferMemory(memory_key=\"chat_history\")\n",
-    "tools = [\n",
-    "    tool\n",
-    "]\n",
-    "\n",
     "agent = initialize_agent(\n",
     "    tools, llm, memory=memory, agent=\"conversational-react-description\", verbose=True\n",
     ")\n",