doc updates (#1639)

---------

Co-authored-by: vbarda <vadym@langchain.dev>

examples/tutorials/sql-agent.ipynb

@@ -39,9 +39,20 @@
     }
    },
    "source": [
-    "## Set up environment\n",
+    "## Setup\n",
     "\n",
-    "We'll set up our environment variables for OpenAI, and optionally, to enable tracing with [LangSmith](https://smith.langchain.com)."
+    "First let's install our required packages and set our API keys"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "id": "4a4be247",
+   "metadata": {},
+   "outputs": [],
+   "source": [
+    "%capture --no-stderr\n",
+    "%pip install -U langgraph langchain_openai langchain_community"
    ]
   },
   {
@@ -60,21 +71,29 @@
    },
    "outputs": [],
    "source": [
+    "import getpass\n",
     "import os\n",
     "\n",
-    "os.environ[\"OPENAI_API_KEY\"] = \"sk-...\"\n",
-    "os.environ[\"LANGSMITH_API_KEY\"] = \"lsv2_pt_...\"\n",
-    "os.environ[\"LANGCHAIN_TRACING_V2\"] = \"true\""
+    "\n",
+    "def _set_env(key: str):\n",
+    "    if key not in os.environ:\n",
+    "        os.environ[key] = getpass.getpass(f\"{key}:\")\n",
+    "\n",
+    "\n",
+    "_set_env(\"OPENAI_API_KEY\")"
    ]
   },
   {
-   "cell_type": "code",
-   "execution_count": 2,
-   "id": "04d73c39-1cc9-4b94-a454-b0a4f604713c",
+   "cell_type": "markdown",
+   "id": "80559636",
    "metadata": {},
-   "outputs": [],
    "source": [
-    "os.environ[\"LANGCHAIN_PROJECT\"] = \"sql-agent\""
+    "<div class=\"admonition tip\">\n",
+    "    <p class=\"admonition-title\">Set up <a href=\"https://smith.langchain.com\">LangSmith</a> for LangGraph development</p>\n",
+    "    <p style=\"padding-top: 5px;\">\n",
+    "        Sign up for LangSmith to quickly spot issues and improve the performance of your LangGraph projects. LangSmith lets you use trace data to debug, test, and monitor your LLM apps built with LangGraph — read more about how to get started <a href=\"https://docs.smith.langchain.com\">here</a>. \n",
+    "    </p>\n",
+    "</div>    "
    ]
   },
   {