If no tool result content, insert an empty json content

Author: jahooma

common/src/util/__tests__/messages.test.ts

@@ -252,6 +252,36 @@ describe('convertCbToModelMessages', () => {
       ])
     })
 
+    it('should convert tool messages with empty content', () => {
+      const messages: Message[] = [
+        {
+          role: 'tool',
+          toolName: 'scraper_page_to_markdown',
+          toolCallId: 'call_empty',
+          content: [],
+        },
+      ]
+
+      const result = convertCbToModelMessages({
+        messages,
+        includeCacheControl: false,
+      })
+
+      expect(result).toEqual([
+        expect.objectContaining({
+          role: 'tool',
+          content: [
+            expect.objectContaining({
+              type: 'tool-result',
+              toolCallId: 'call_empty',
+              toolName: 'scraper_page_to_markdown',
+              output: { type: 'json', value: '(empty result)' },
+            } satisfies ToolResultPart),
+          ],
+        }),
+      ])
+    })
+
     it('should handle multiple tool outputs', () => {
       const messages: Message[] = [
         {

common/src/util/messages.ts

@@ -126,6 +126,21 @@ function assistantToCodebuffMessage(
 function convertToolResultMessage(
   message: ToolMessage,
 ): ModelMessageWithAuxiliaryData[] {
+  if (message.content.length === 0) {
+    return [
+      cloneDeep<ToolModelMessage>({
+        ...message,
+        role: 'tool',
+        content: [
+          {
+            ...message,
+            output: { type: 'json', value: '' },
+            type: 'tool-result',
+          },
+        ],
+      }),
+    ]
+  }
   return message.content.map((c) => {
     if (c.type === 'json') {
       return cloneDeep<ToolModelMessage>({
@@ -326,8 +341,8 @@ export function convertCbToModelMessages({
       }
       throw new Error(
         `convertCbToModelMessages: Message at index ${i} failed schema validation.\n` +
-          `Role: ${message.role}\n` +
-          `Message:\n${result.error.message}`,
+        `Role: ${message.role}\n` +
+        `Message:\n${result.error.message}`,
       )
     }
   }
@@ -356,8 +371,8 @@ export function systemMessage(
   params:
     | SystemContent
     | ({
-        content: SystemContent
-      } & Omit<SystemMessage, 'role' | 'content'>),
+      content: SystemContent
+    } & Omit<SystemMessage, 'role' | 'content'>),
 ): SystemMessage {
   if (typeof params === 'object' && 'content' in params) {
     return {
@@ -390,8 +405,8 @@ export function userMessage(
   params:
     | UserContent
     | ({
-        content: UserContent
-      } & Omit<UserMessage, 'role' | 'content'>),
+      content: UserContent
+    } & Omit<UserMessage, 'role' | 'content'>),
 ): UserMessage {
   if (typeof params === 'object' && 'content' in params) {
     return {
@@ -428,8 +443,8 @@ export function assistantMessage(
   params:
     | AssistantContent
     | ({
-        content: AssistantContent
-      } & Omit<AssistantMessage, 'role' | 'content'>),
+      content: AssistantContent
+    } & Omit<AssistantMessage, 'role' | 'content'>),
 ): AssistantMessage {
   if (typeof params === 'object' && 'content' in params) {
     return {
@@ -449,10 +464,10 @@ export function assistantMessage(
 export function jsonToolResult<T extends JSONValue>(
   value: T,
 ): [
-  Extract<ToolResultOutput, { type: 'json' }> & {
-    value: T
-  },
-] {
+    Extract<ToolResultOutput, { type: 'json' }> & {
+      value: T
+    },
+  ] {
   return [
     {
       type: 'json',