cloudflare[minor]: Add tool calling support

docs/core_docs/docs/integrations/chat/cloudflare_workersai.mdx

@@ -26,3 +26,15 @@ import UnifiedModelParamsTooltip from "@mdx_components/unified_model_params_tool
 <UnifiedModelParamsTooltip></UnifiedModelParamsTooltip>
 
 <CodeBlock language="typescript">{Example}</CodeBlock>
+
+### Tool calling
+
+:::note
+Tool calling is only available in `@langchain/cloudflare` version `0.0.7` and above.
+:::
+
+Cloudflare's API now supports tool calling! The below example demonstrates how to invoke and stream tool calls.
+
+import ToolCalling from "@examples/models/chat/integration_cloudflare_tools.ts";
+
+<CodeBlock language="typescript">{ToolCalling}</CodeBlock>

examples/src/models/chat/integration_cloudflare_tools.ts

@@ -0,0 +1,101 @@
+import { ChatCloudflareWorkersAI } from "@langchain/cloudflare";
+import {
+  AIMessageChunk,
+  HumanMessage,
+  SystemMessage,
+} from "@langchain/core/messages";
+import { tool } from "@langchain/core/tools";
+import { z } from "zod";
+
+const model = new ChatCloudflareWorkersAI({
+  model: "@hf/nousresearch/hermes-2-pro-mistral-7b",
+  cloudflareAccountId: process.env.CLOUDFLARE_ACCOUNT_ID,
+  cloudflareApiToken: process.env.CLOUDFLARE_API_TOKEN,
+  // Pass a custom base URL to use Cloudflare AI Gateway
+  // baseUrl: `https://gateway.ai.cloudflare.com/v1/{YOUR_ACCOUNT_ID}/{GATEWAY_NAME}/workers-ai/`,
+});
+
+const weatherSchema = z.object({
+  location: z.string().describe("The location to get the weather for"),
+});
+const weatherTool = tool<typeof weatherSchema>(
+  (input) => {
+    return `The weather in ${input.location} is sunny.`;
+  },
+  {
+    name: "get_weather",
+    description: "Get the weather",
+  }
+);
+
+const modelWithTools = model.bindTools([weatherTool]);
+
+const inputMessages = [
+  new SystemMessage("You are a helpful assistant."),
+  new HumanMessage("What's the weather like in the North Pole?"),
+];
+
+const response = await modelWithTools.invoke(inputMessages);
+
+console.log(response.tool_calls);
+
+/*
+[ { name: 'get_weather', args: { input: 'North Pole' } } ]
+*/
+
+const stream = await modelWithTools.stream(inputMessages);
+
+let finalChunk: AIMessageChunk | undefined;
+for await (const chunk of stream) {
+  console.log("chunk: ", chunk.content);
+  if (!finalChunk) {
+    finalChunk = chunk;
+  } else {
+    finalChunk = finalChunk.concat(chunk);
+  }
+}
+
+/*
+chunk:  <
+chunk:  tool
+chunk:  _
+chunk:  call
+chunk:  >
+chunk:  \n
+chunk:  {'
+chunk:  arguments
+chunk:  ':
+chunk:   {'
+chunk:  input
+chunk:  ':
+chunk:   '
+chunk:  N
+chunk:  orth
+chunk:   P
+chunk:  ole
+chunk:  '},
+chunk:   '
+chunk:  name
+chunk:  ':
+chunk:   '
+chunk:  get
+chunk:  _
+chunk:  we
+chunk:  ather
+chunk:  '}
+chunk:  \n
+chunk:  </
+chunk:  tool
+chunk:  _
+chunk:  call
+chunk:  >
+chunk:  <|im_end|>
+*/
+
+console.log(finalChunk?.tool_calls);
+
+/*
+[
+  { name: 'get_weather', args: { input: 'North Pole' }, id: undefined }
+]
+*/

libs/langchain-cloudflare/package.json

@@ -37,7 +37,8 @@
   "dependencies": {
     "@cloudflare/ai": "^1.0.47",
     "@langchain/core": ">0.1.0 <0.3.0",
-    "uuid": "^9.0.1"
+    "uuid": "^9.0.1",
+    "zod-to-json-schema": "^3.22.3"
   },
   "devDependencies": {
     "@cloudflare/workers-types": "^4.20231218.0",
@@ -64,7 +65,8 @@
     "release-it": "^15.10.1",
     "rollup": "^4.5.2",
     "ts-jest": "^29.1.0",
-    "typescript": "<5.2.0"
+    "typescript": "<5.2.0",
+    "zod": "^3.22.4"
   },
   "publishConfig": {
     "access": "public"