core[patch]: Add check for bind tools in structured prompt (#5882)

* core[patch]: Add check for bind tools in structured promot

* cr

* fix test

Author: bracesproul

langchain-core/src/prompts/structured.ts

@@ -1,3 +1,5 @@
+import { BaseLanguageModel } from "../language_models/base.js";
+import { BaseChatModel } from "../language_models/chat_models.js";
 import { ChatPromptValueInterface } from "../prompt_values.js";
 import {
   RunnableLike,
@@ -22,7 +24,18 @@ function isWithStructuredOutput(
     typeof x === "object" &&
     x != null &&
     "withStructuredOutput" in x &&
-    typeof x.withStructuredOutput === "function"
+    x.withStructuredOutput !== BaseLanguageModel.prototype.withStructuredOutput
+  );
+}
+
+function isBindTools(x: unknown): x is {
+  bindTools: (...arg: unknown[]) => Runnable;
+} {
+  return (
+    typeof x === "object" &&
+    x != null &&
+    "bindTools" in x &&
+    x.bindTools !== BaseChatModel.prototype.bindTools
   );
 }
 
@@ -84,7 +97,8 @@ export class StructuredPrompt<
 
     if (
       isRunnableBinding(coerceable) &&
-      isWithStructuredOutput(coerceable.bound)
+      isWithStructuredOutput(coerceable.bound) &&
+      isBindTools(coerceable.bound)
     ) {
       return super.pipe(
         coerceable.bound

langchain-core/src/prompts/tests/structured.test.ts

@@ -4,15 +4,23 @@ import {
   StructuredOutputMethodParams,
   StructuredOutputMethodOptions,
   BaseLanguageModelInput,
+  ToolDefinition,
 } from "../../language_models/base.js";
 import { BaseMessage } from "../../messages/index.js";
 import { Runnable, RunnableLambda } from "../../runnables/base.js";
 import { RunnableConfig } from "../../runnables/config.js";
 import { FakeListChatModel } from "../../utils/testing/index.js";
 import { StructuredPrompt } from "../structured.js";
 import { load } from "../../load/index.js";
+import { StructuredToolInterface } from "../../tools.js";
 
 class FakeStructuredChatModel extends FakeListChatModel {
+  override bindTools(
+    _tools: (StructuredToolInterface | ToolDefinition | Record<string, any>)[]
+  ): Runnable {
+    return this.bind({});
+  }
+
   withStructuredOutput<
     RunOutput extends Record<string, any> = Record<string, any>
   >(