fix(core): preserve multimodal content parts in DashScope tool result…

agentscope-core/src/main/java/io/agentscope/core/formatter/dashscope/DashScopeMessageConverter.java

@@ -168,9 +168,12 @@ private DashScopeMessage convertToMultimodalContent(Msg msg) {
     private DashScopeMessage convertToolRoleMessage(Msg msg) {
         ToolResultBlock toolResult = msg.getFirstContentBlock(ToolResultBlock.class);
         if (toolResult != null) {
-            String toolResultText = toolResultConverter.apply(toolResult.getOutput());
-            List<DashScopeContentPart> content = new ArrayList<>();
-            content.add(DashScopeContentPart.text(toolResultText));
+            List<DashScopeContentPart> content =
+                    hasMediaContent(toolResult.getOutput())
+                            ? convertContentBlocks(toolResult.getOutput())
+                            : List.of(
+                                    DashScopeContentPart.text(
+                                            toolResultConverter.apply(toolResult.getOutput())));
 
             return DashScopeMessage.builder()
                     .role("tool")
@@ -181,9 +184,10 @@ private DashScopeMessage convertToolRoleMessage(Msg msg) {
         }
 
         // Fallback: no ToolResultBlock found, use text content
-        List<DashScopeContentPart> content = new ArrayList<>();
-        content.add(DashScopeContentPart.text(extractTextContent(msg)));
-        return DashScopeMessage.builder().role("tool").content(content).build();
+        return DashScopeMessage.builder()
+                .role("tool")
+                .content(List.of(DashScopeContentPart.text(extractTextContent(msg))))
+                .build();
     }
 
     /**
@@ -260,4 +264,58 @@ private void applyCacheControlFromMetadata(Msg msg, DashScopeMessage result) {
             result.setCacheControl(DashScopeChatFormatter.getEphemeralCacheControl());
         }
     }
+
+    /**
+     * Check if blocks contain media content (image, audio, video).
+     *
+     * @param blocks the list of content blocks to check
+     * @return true if any block is ImageBlock, AudioBlock, or VideoBlock
+     */
+    private boolean hasMediaContent(List<ContentBlock> blocks) {
+        if (blocks == null) {
+            return false;
+        }
+        for (ContentBlock block : blocks) {
+            if (block instanceof ImageBlock
+                    || block instanceof AudioBlock
+                    || block instanceof VideoBlock) {
+                return true;
+            }
+        }
+        return false;
+    }
+
+    /**
+     * Convert content blocks to DashScope content parts for multimodal messages.
+     *
+     * @param blocks the list of content blocks to convert
+     * @return the converted list of DashScopeContentPart
+     */
+    private List<DashScopeContentPart> convertContentBlocks(List<ContentBlock> blocks) {
+        List<DashScopeContentPart> content = new ArrayList<>();
+        for (ContentBlock block : blocks) {
+            if (block instanceof TextBlock tb) {
+                content.add(DashScopeContentPart.text(tb.getText()));
+            } else if (block instanceof ImageBlock ib) {
+                try {
+                    content.add(mediaConverter.convertImageBlockToContentPart(ib));
+                } catch (Exception e) {
+                    log.warn("Failed to process ImageBlock in tool result: {}", e.getMessage());
+                }
+            } else if (block instanceof AudioBlock ab) {
+                try {
+                    content.add(mediaConverter.convertAudioBlockToContentPart(ab));
+                } catch (Exception e) {
+                    log.warn("Failed to process AudioBlock in tool result: {}", e.getMessage());
+                }
+            } else if (block instanceof VideoBlock vb) {
+                try {
+                    content.add(mediaConverter.convertVideoBlockToContentPart(vb));
+                } catch (Exception e) {
+                    log.warn("Failed to process VideoBlock in tool result: {}", e.getMessage());
+                }
+            }
+        }
+        return content;
+    }
 }

agentscope-core/src/test/java/io/agentscope/core/formatter/DashScopeChatFormatterGroundTruthTest.java

@@ -341,13 +341,8 @@ private static void buildGroundTruth() {
                         .build());
 
         // Message 8: Tool result
-        String toolResultContent =
-                "- The capital of Japan is Tokyo.\n"
-                        + "- The returned image can be found at: "
-                        + imagePath
-                        + "\n"
-                        + "- The returned audio can be found at: "
-                        + mockAudioPath;
+        File imageFile2 = new File(imagePath);
+        String absoluteImagePath2 = "file://" + imageFile2.getAbsolutePath();
         groundTruthChat.add(
                 DashScopeMessage.builder()
                         .role("tool")
@@ -356,7 +351,15 @@ private static void buildGroundTruth() {
                         .content(
                                 List.of(
                                         DashScopeContentPart.builder()
-                                                .text(toolResultContent)
+                                                .text("The capital of Japan is Tokyo.")
+                                                .build(),
+                                        DashScopeContentPart.builder()
+                                                .image(absoluteImagePath2)
+                                                .build(),
+                                        DashScopeContentPart.builder()
+                                                .audio(
+                                                        "data:audio/wav;base64,"
+                                                                + "ZmFrZSBhdWRpbyBjb250ZW50")
                                                 .build()))
                         .build());
 

agentscope-core/src/test/java/io/agentscope/core/formatter/DashScopeMultiAgentFormatterGroundTruthTest.java

@@ -391,20 +391,18 @@ private static void buildGroundTruth() {
                         .build());
 
         // Message 4: Tool result
-        String toolResultContent =
-                "- The capital of Japan is Tokyo.\n"
-                        + "- The returned image can be found at: "
-                        + imagePath
-                        + "\n"
-                        + "- The returned audio can be found at: "
-                        + mockAudioPath;
-        DashScopeContentPart toolContent = DashScopeContentPart.text(toolResultContent);
+        List<DashScopeContentPart> toolResultParts =
+                List.of(
+                        DashScopeContentPart.text("The capital of Japan is Tokyo."),
+                        DashScopeContentPart.image(absoluteImagePath),
+                        DashScopeContentPart.audio(
+                                "data:audio/wav;base64," + "ZmFrZSBhdWRpbyBjb250ZW50"));
         groundTruthMultiagent.add(
                 DashScopeMessage.builder()
                         .role("tool")
                         .toolCallId("1")
                         .name("get_capital")
-                        .content(List.of(toolContent))
+                        .content(toolResultParts)
                         .build());
 
         // Message 5: User with assistant response in history
@@ -435,7 +433,7 @@ private static void buildGroundTruth() {
                         .role("tool")
                         .toolCallId("1")
                         .name("get_capital")
-                        .content(List.of(toolContent))
+                        .content(toolResultParts)
                         .build());
 
         // Message 4: User with history
@@ -475,7 +473,7 @@ private static void buildGroundTruth() {
                         .role("tool")
                         .toolCallId("1")
                         .name("get_capital")
-                        .content(List.of(toolContent))
+                        .content(toolResultParts)
                         .build());
 
         // Message 5: User with updated history including second conversation
@@ -508,20 +506,17 @@ private static void buildGroundTruth() {
                         .build());
 
         // Message 7: Second tool result (note: tool_call_id is "2")
-        String toolResultContent2 =
-                "- The capital of South Korea is Seoul.\n"
-                        + "- The returned image can be found at: "
-                        + imagePath
-                        + "\n"
-                        + "- The returned audio can be found at: "
-                        + mockAudioPath;
-        DashScopeContentPart toolContent2 = DashScopeContentPart.text(toolResultContent2);
+        DashScopeContentPart toolContent2 =
+                DashScopeContentPart.text("The capital of South Korea is Seoul.");
+        DashScopeContentPart toolImageContent2 = DashScopeContentPart.image(absoluteImagePath);
+        DashScopeContentPart toolAudioContent2 =
+                DashScopeContentPart.audio("data:audio/wav;base64," + "ZmFrZSBhdWRpbyBjb250ZW50");
         groundTruthMultiagent2.add(
                 DashScopeMessage.builder()
                         .role("tool")
                         .toolCallId("2")
                         .name("get_capital")
-                        .content(List.of(toolContent2))
+                        .content(List.of(toolContent2, toolImageContent2, toolAudioContent2))
                         .build());
 
         // Message 8: Final user with last response in history

agentscope-core/src/test/java/io/agentscope/core/formatter/dashscope/DashScopeMessageConverterTest.java

@@ -563,4 +563,118 @@ void testToolCallFallbackToInputMapWhenContentEmpty() {
         assertTrue(args.contains("city"));
         assertTrue(args.contains("Shanghai"));
     }
+
+    @Test
+    void testToolResultWithImageBlock() {
+        DashScopeMessageConverter conv =
+                new DashScopeMessageConverter(
+                        blocks -> {
+                            StringBuilder sb = new StringBuilder();
+                            for (ContentBlock block : blocks) {
+                                if (block instanceof TextBlock tb) {
+                                    if (!sb.isEmpty()) {
+                                        sb.append("\n");
+                                    }
+                                    sb.append(tb.getText());
+                                } else if (block instanceof ImageBlock) {
+                                    if (!sb.isEmpty()) {
+                                        sb.append("\n");
+                                    }
+                                    sb.append("The returned image can be found at: /tmp/test.png");
+                                }
+                            }
+                            return sb.toString();
+                        });
+
+        ToolResultBlock toolResult =
+                ToolResultBlock.builder()
+                        .id("call_123")
+                        .name("get_image")
+                        .output(
+                                List.of(
+                                        TextBlock.builder().text("Here is a cat image").build(),
+                                        ImageBlock.builder()
+                                                .source(
+                                                        URLSource.builder()
+                                                                .url(
+                                                                        "https://agentscope-test.oss-cn-beijing.aliyuncs.com/Cat03.jpg")
+                                                                .build())
+                                                .build()))
+                        .build();
+
+        Msg msg = Msg.builder().role(MsgRole.TOOL).content(List.of(toolResult)).build();
+        DashScopeMessage dsMsg = conv.convertToMessage(msg, true);
+
+        assertEquals("tool", dsMsg.getRole());
+        assertEquals("call_123", dsMsg.getToolCallId());
+        assertTrue(dsMsg.isMultimodal());
+        assertEquals(2, dsMsg.getContentAsList().size());
+    }
+
+    @Test
+    void testToolResultWithTextImageAudioBlocks() {
+        // Test that tool result with TextBlock + ImageBlock + AudioBlock returns 3 content parts
+        DashScopeMessageConverter conv =
+                new DashScopeMessageConverter(
+                        blocks -> {
+                            StringBuilder sb = new StringBuilder();
+                            for (ContentBlock block : blocks) {
+                                if (block instanceof TextBlock tb) {
+                                    if (!sb.isEmpty()) {
+                                        sb.append("\n");
+                                    }
+                                    sb.append(tb.getText());
+                                } else if (block instanceof ImageBlock) {
+                                    if (!sb.isEmpty()) {
+                                        sb.append("\n");
+                                    }
+                                    sb.append("The returned image can be found at: /tmp/test.png");
+                                } else if (block instanceof AudioBlock) {
+                                    if (!sb.isEmpty()) {
+                                        sb.append("\n");
+                                    }
+                                    sb.append("The returned audio can be found at: /tmp/test.wav");
+                                }
+                            }
+                            return sb.toString();
+                        });
+
+        ToolResultBlock toolResult =
+                ToolResultBlock.builder()
+                        .id("call_multi_media")
+                        .name("get_multimodal")
+                        .output(
+                                List.of(
+                                        TextBlock.builder()
+                                                .text("The capital of Japan is Tokyo.")
+                                                .build(),
+                                        ImageBlock.builder()
+                                                .source(
+                                                        URLSource.builder()
+                                                                .url(
+                                                                        "https://example.com/image.png")
+                                                                .build())
+                                                .build(),
+                                        AudioBlock.builder()
+                                                .source(
+                                                        URLSource.builder()
+                                                                .url(
+                                                                        "https://example.com/audio.wav")
+                                                                .build())
+                                                .build()))
+                        .build();
+
+        Msg msg = Msg.builder().role(MsgRole.TOOL).content(List.of(toolResult)).build();
+        DashScopeMessage dsMsg = conv.convertToMessage(msg, true);
+
+        assertEquals("tool", dsMsg.getRole());
+        assertEquals("call_multi_media", dsMsg.getToolCallId());
+        assertEquals("get_multimodal", dsMsg.getName());
+        assertTrue(dsMsg.isMultimodal());
+        // Should preserve all 3 content parts: text, image, audio
+        assertEquals(3, dsMsg.getContentAsList().size());
+        assertEquals("The capital of Japan is Tokyo.", dsMsg.getContentAsList().get(0).getText());
+        assertEquals("https://example.com/image.png", dsMsg.getContentAsList().get(1).getImage());
+        assertEquals("https://example.com/audio.wav", dsMsg.getContentAsList().get(2).getAudio());
+    }
 }