From 11b7b82b2192d0d752bcdb4a858aafcc20b74cf5 Mon Sep 17 00:00:00 2001
From: jacoblee93 <jacoblee93@gmail.com>
Date: Wed, 10 Apr 2024 16:14:47 -0700
Subject: [PATCH] Only populate tool params if sensible

---
 libs/langchain-anthropic/src/chat_models.ts   | 45 +++++++++++--------
 .../src/tests/chat_models-tools.int.test.ts   | 20 +++++----
 2 files changed, 38 insertions(+), 27 deletions(-)

diff --git a/libs/langchain-anthropic/src/chat_models.ts b/libs/langchain-anthropic/src/chat_models.ts
index ae8db9c80b80..6a8253b51593 100644
--- a/libs/langchain-anthropic/src/chat_models.ts
+++ b/libs/langchain-anthropic/src/chat_models.ts
@@ -331,29 +331,35 @@ function _formatMessagesForAnthropic(messages: BaseMessage[]): {
       throw new Error(`Message type "${message._getType()}" is not supported.`);
     }
     if (isAIMessage(message) && !!message.tool_calls?.length) {
-      const rawContent = _formatContent(message.content);
-      if (typeof rawContent === "string") {
+      if (message.content === "") {
         return {
           role,
-          content: [
-            { type: "text", text: rawContent },
-            ...message.tool_calls.map(_convertLangChainToolCallToAnthropic),
-          ],
+          content: message.tool_calls.map(_convertLangChainToolCallToAnthropic),
+        };
+      } else if (typeof message.content === "string") {
+        console.warn(
+          `The "tool_calls" field on a message is only respected if content is an empty string.`
+        );
+        return {
+          role,
+          content: _formatContent(message.content),
         };
       } else {
-        const missingToolCallBlocks = message.tool_calls.filter(
-          (toolCall) =>
-            !!rawContent.find(
-              (contentPart) =>
-                contentPart === "tool_use" && toolCall.id === contentPart.id
-            )
+        const { content } = message;
+        const hasMismatchedToolCalls = !message.tool_calls.every((toolCall) =>
+          content.find(
+            (contentPart) =>
+              contentPart.type === "tool_use" && contentPart.id === toolCall.id
+          )
         );
+        if (hasMismatchedToolCalls) {
+          console.warn(
+            `The "tool_calls" field on a message is only respected if content is an empty string.`
+          );
+        }
         return {
           role,
-          content: [
-            ...rawContent,
-            ...missingToolCallBlocks.map(_convertLangChainToolCallToAnthropic),
-          ],
+          content: _formatContent(message.content),
         };
       }
     } else {
@@ -601,11 +607,12 @@ export class ChatAnthropicMessages<
     runManager?: CallbackManagerForLLMRun
   ): AsyncGenerator<ChatGenerationChunk> {
     const params = this.invocationParams(options);
+    const formattedMessages = _formatMessagesForAnthropic(messages);
     const requestOptions = this.invocationOptions(
       {
         ...params,
         stream: false,
-        ..._formatMessagesForAnthropic(messages),
+        ...formattedMessages,
       },
       options
     );
@@ -614,7 +621,7 @@ export class ChatAnthropicMessages<
         {
           ...params,
           stream: false,
-          ..._formatMessagesForAnthropic(messages),
+          ...formattedMessages,
         },
         options
       );
@@ -644,7 +651,7 @@ export class ChatAnthropicMessages<
       const stream = await this.createStreamWithRetry(
         {
           ...params,
-          ..._formatMessagesForAnthropic(messages),
+          ...formattedMessages,
           stream: true,
         },
         requestOptions
diff --git a/libs/langchain-anthropic/src/tests/chat_models-tools.int.test.ts b/libs/langchain-anthropic/src/tests/chat_models-tools.int.test.ts
index 87447b1e681d..b5be633974e0 100644
--- a/libs/langchain-anthropic/src/tests/chat_models-tools.int.test.ts
+++ b/libs/langchain-anthropic/src/tests/chat_models-tools.int.test.ts
@@ -58,11 +58,11 @@ test("Few shotting with tool calls", async () => {
   const res = await chat.invoke([
     new HumanMessage("What is the weather in SF?"),
     new AIMessage({
-      content: "Let me look that up!",
+      content: "",
       tool_calls: [
         {
           id: "toolu_feiwjf9u98r389u498",
-          name: "get_current_weather",
+          name: "get_weather",
           args: {
             location: "SF",
           },
@@ -88,7 +88,7 @@ test("Can bind & invoke StructuredTools", async () => {
   const modelWithTools = model.bindTools(tools);
 
   const result = await modelWithTools.invoke(
-    "What is the weather in London today?"
+    "What is the weather in SF today?"
   );
   console.log(
     {
@@ -116,17 +116,21 @@ test("Can bind & invoke StructuredTools", async () => {
   expect(input).toBeTruthy();
   expect(input.location).toBeTruthy();
   const result2 = await modelWithTools.invoke([
-    new HumanMessage("What is the weather in London today?"),
+    new HumanMessage("What is the weather in SF today?"),
     result,
     new ToolMessage({
       tool_call_id: result.tool_calls?.[0].id ?? "",
-      content: "The weather in London is currently 98 degrees and sunny.",
+      content:
+        "The weather in San Francisco is currently 59 degrees and sunny.",
     }),
-    new AIMessage("The weather in London is currently 98 degrees and sunny."),
-    new HumanMessage("What did you just say the weather was?"),
+    new AIMessage(
+      "The weather in San Francisco is currently 59 degrees and sunny."
+    ),
+    new HumanMessage("What did you say the weather was?"),
   ]);
   console.log(result2);
-  expect(result2.content).toContain("98");
+  // This should work, but Anthorpic is too skeptical
+  expect(result2.content).toContain("59");
 });
 
 test("Can bind & invoke AnthropicTools", async () => {