diff --git a/lib/langchain/assistant.rb b/lib/langchain/assistant.rb
index 25411fff..5395fae1 100644
--- a/lib/langchain/assistant.rb
+++ b/lib/langchain/assistant.rb
@@ -173,11 +173,12 @@ def add_message_and_run!(content: nil, image_url: nil)
     # Submit tool output
     #
     # @param tool_call_id [String] The ID of the tool call to submit output for
-    # @param output [String] The output of the tool
+    # @param content [String] The content of the tool call
+    # @param image_url [String] The image URL of the tool call
     # @return [Array<Langchain::Message>] The messages
-    def submit_tool_output(tool_call_id:, output:)
+    def submit_tool_output(tool_call_id:, content:, image_url: nil)
       # TODO: Validate that `tool_call_id` is valid by scanning messages and checking if this tool call ID was invoked
-      add_message(role: @llm_adapter.tool_role, content: output, tool_call_id: tool_call_id)
+      add_message(role: @llm_adapter.tool_role, content: content, tool_call_id: tool_call_id, image_url: image_url)
     end
 
     # Delete all messages
@@ -371,9 +372,9 @@ def run_tool(tool_call)
 
       # Call the callback if set
       tool_execution_callback.call(tool_call_id, tool_name, method_name, tool_arguments) if tool_execution_callback # rubocop:disable Style/SafeNavigation
-      output = tool_instance.send(method_name, **tool_arguments)
+      content, image_url = tool_instance.send(method_name, **tool_arguments)
 
-      submit_tool_output(tool_call_id: tool_call_id, output: output)
+      submit_tool_output(tool_call_id: tool_call_id, content: content, image_url: image_url)
     end
 
     # Build a message
diff --git a/lib/langchain/assistant/messages/anthropic_message.rb b/lib/langchain/assistant/messages/anthropic_message.rb
index 70f38209..1285cfeb 100644
--- a/lib/langchain/assistant/messages/anthropic_message.rb
+++ b/lib/langchain/assistant/messages/anthropic_message.rb
@@ -76,7 +76,7 @@ def tool_hash
               {
                 type: "tool_result",
                 tool_use_id: tool_call_id,
-                content: content
+                content: build_content_array
               }
             ]
           }
diff --git a/lib/langchain/assistant/messages/mistral_ai_message.rb b/lib/langchain/assistant/messages/mistral_ai_message.rb
index 2c081d94..ba3de404 100644
--- a/lib/langchain/assistant/messages/mistral_ai_message.rb
+++ b/lib/langchain/assistant/messages/mistral_ai_message.rb
@@ -102,7 +102,7 @@ def system_hash
         def tool_hash
           {
             role: "tool",
-            content: content,
+            content: build_content_array,
             tool_call_id: tool_call_id
           }
         end
diff --git a/lib/langchain/assistant/messages/openai_message.rb b/lib/langchain/assistant/messages/openai_message.rb
index 44e57a34..e19b1246 100644
--- a/lib/langchain/assistant/messages/openai_message.rb
+++ b/lib/langchain/assistant/messages/openai_message.rb
@@ -117,7 +117,7 @@ def tool_hash
           {
             role: "tool",
             tool_call_id: tool_call_id,
-            content: build_content_array
+            content: build_content_array # Using image_url with tools is not supported by OpenAI (Image URLs are only allowed for messages with role 'user', but this message with role 'tool' contains an image URL.)
           }
         end
 
diff --git a/spec/langchain/assistant/assistant_spec.rb b/spec/langchain/assistant/assistant_spec.rb
index 432d4df9..e5e96640 100644
--- a/spec/langchain/assistant/assistant_spec.rb
+++ b/spec/langchain/assistant/assistant_spec.rb
@@ -197,10 +197,17 @@
 
     describe "#submit_tool_output" do
       it "adds a message to the thread" do
-        subject.submit_tool_output(tool_call_id: "123", output: "bar")
+        subject.submit_tool_output(tool_call_id: "123", content: "bar")
         expect(subject.messages.last.role).to eq("tool")
         expect(subject.messages.last.content).to eq("bar")
       end
+
+      it "adds an image to the message" do
+        subject.submit_tool_output(tool_call_id: "123", image_url: "https://example.com/image.jpg", content: "Hello")
+        expect(subject.messages.last.role).to eq("tool")
+        expect(subject.messages.last.content).to eq("Hello")
+        expect(subject.messages.last.image_url).to eq("https://example.com/image.jpg")
+      end
     end
 
     describe "#run" do
@@ -564,10 +571,17 @@
 
     describe "#submit_tool_output" do
       it "adds a message to the thread" do
-        subject.submit_tool_output(tool_call_id: "123", output: "bar")
+        subject.submit_tool_output(tool_call_id: "123", content: "bar")
         expect(subject.messages.last.role).to eq("tool")
         expect(subject.messages.last.content).to eq("bar")
       end
+
+      it "adds an image to the message" do
+        subject.submit_tool_output(tool_call_id: "123", image_url: "https://example.com/image.jpg", content: "Hello")
+        expect(subject.messages.last.role).to eq("tool")
+        expect(subject.messages.last.content).to eq("Hello")
+        expect(subject.messages.last.image_url).to eq("https://example.com/image.jpg")
+      end
     end
 
     describe "#run" do
@@ -658,7 +672,7 @@
                     "type" => "function"
                   }
                 ]},
-                {content: "4.0", role: "tool", tool_call_id: "call_9TewGANaaIjzY31UCpAAGLeV"}
+                {content: [{type: "text", text: "4.0"}], role: "tool", tool_call_id: "call_9TewGANaaIjzY31UCpAAGLeV"}
               ],
               tools: calculator.class.function_schemas.to_openai_format,
               tool_choice: "auto"
@@ -916,12 +930,19 @@
       end
     end
 
-    describe "submit_tool_output" do
+    describe "#submit_tool_output" do
       it "adds a message to the thread" do
-        subject.submit_tool_output(tool_call_id: "123", output: "bar")
+        subject.submit_tool_output(tool_call_id: "123", content: "bar")
         expect(subject.messages.last.role).to eq("function")
         expect(subject.messages.last.content).to eq("bar")
       end
+
+      it "does not add image to the message" do
+        subject.submit_tool_output(tool_call_id: "123", content: "Hello", image_url: "https://example.com/image.jpg")
+        expect(subject.messages.last.role).to eq("function")
+        expect(subject.messages.last.content).to eq("Hello")
+        expect(subject.messages.last.image_url).to be_nil
+      end
     end
 
     describe "#run" do
@@ -1100,7 +1121,7 @@
 
     describe "submit_tool_output" do
       it "adds a message to the thread" do
-        subject.submit_tool_output(tool_call_id: "123", output: "bar")
+        subject.submit_tool_output(tool_call_id: "123", content: "bar")
         expect(subject.messages.last.role).to eq("tool_result")
         expect(subject.messages.last.content).to eq("bar")
       end
@@ -1218,7 +1239,7 @@
                     "input" => {"input" => "2+2"}
                   }
                 ]},
-                {role: "user", content: [{type: "tool_result", tool_use_id: "toolu_014eSx9oBA5DMe8gZqaqcJ3H", content: "4.0"}]}
+                {role: "user", content: [{type: "tool_result", tool_use_id: "toolu_014eSx9oBA5DMe8gZqaqcJ3H", content: [{type: "text", text: "4.0"}]}]}
               ],
               tools: calculator.class.function_schemas.to_anthropic_format,
               tool_choice: {disable_parallel_tool_use: false, type: "auto"},
diff --git a/spec/langchain/assistant/messages/anthropic_message_spec.rb b/spec/langchain/assistant/messages/anthropic_message_spec.rb
index a1f04924..ef8f132a 100644
--- a/spec/langchain/assistant/messages/anthropic_message_spec.rb
+++ b/spec/langchain/assistant/messages/anthropic_message_spec.rb
@@ -108,12 +108,42 @@
               {
                 type: "tool_result",
                 tool_use_id: "toolu_014eSx9oBA5DMe8gZqaqcJ3H",
-                content: "4.0"
+                content: [
+                  {
+                    type: "text",
+                    text: "4.0"
+                  }
+                ]
               }
             ]
           }
         )
       end
+
+      it "returns tool_hash with image_url" do
+        message = described_class.new(role: "tool_result", image_url: "https://example.com/image.jpg")
+        allow(message).to receive(:image).and_return(double(base64: "base64_data", mime_type: "image/jpeg"))
+
+        expect(message.to_hash).to eq(
+          role: "user",
+          content: [
+            {
+              type: "tool_result",
+              tool_use_id: nil,
+              content: [
+                {
+                  type: "image",
+                  source: {
+                    type: "base64",
+                    data: "base64_data",
+                    media_type: "image/jpeg"
+                  }
+                }
+              ]
+            }
+          ]
+        )
+      end
     end
 
     context "when role is user" do
diff --git a/spec/langchain/assistant/messages/mistral_ai_message_spec.rb b/spec/langchain/assistant/messages/mistral_ai_message_spec.rb
index 9f4af833..d979a90f 100644
--- a/spec/langchain/assistant/messages/mistral_ai_message_spec.rb
+++ b/spec/langchain/assistant/messages/mistral_ai_message_spec.rb
@@ -18,7 +18,7 @@
       let(:message) { described_class.new(role: "tool", content: "Hello, world!", tool_calls: [], tool_call_id: "123") }
 
       it "returns a hash with the tool_call_id key" do
-        expect(message.to_hash).to eq({role: "tool", content: "Hello, world!", tool_call_id: "123"})
+        expect(message.to_hash).to eq({role: "tool", content: [{text: "Hello, world!", type: "text"}], tool_call_id: "123"})
       end
     end
 
@@ -36,7 +36,7 @@
       end
     end
 
-    context "when image_url is present" do
+    context "when image_url is present in user message" do
       let(:message) { described_class.new(role: "user", content: "Please describe this image", image_url: "https://example.com/image.jpg") }
 
       it "returns a hash with the image_url key" do
@@ -49,5 +49,26 @@
         })
       end
     end
+
+    context "when image_url is present in tool message" do
+      let(:tool_call) {
+        {"id" => "call_9TewGANaaIjzY31UCpAAGLeV",
+         "type" => "function",
+         "function" => {"name" => "dummy_tool__take_photo"}}
+      }
+
+      let(:message) { described_class.new(role: "tool", content: "Hello, world!", image_url: "https://example.com/image.jpg", tool_calls: [tool_call], tool_call_id: "123") }
+
+      it "returns a hash with the image_url key" do
+        expect(message.to_hash).to eq({
+          role: "tool",
+          content: [
+            {text: "Hello, world!", type: "text"},
+            {image_url: "https://example.com/image.jpg", type: "image_url"}
+          ],
+          tool_call_id: "123"
+        })
+      end
+    end
   end
 end
diff --git a/spec/langchain/assistant/messages/openai_message_spec.rb b/spec/langchain/assistant/messages/openai_message_spec.rb
index 6e74bf68..e089053c 100644
--- a/spec/langchain/assistant/messages/openai_message_spec.rb
+++ b/spec/langchain/assistant/messages/openai_message_spec.rb
@@ -43,6 +43,21 @@
       it "returns a tool_hash" do
         expect(message.to_hash).to eq({role: "tool", content: [{type: "text", text: "Hello, world!"}], tool_call_id: "123"})
       end
+
+      context "when image_url is present" do
+        let(:message) { described_class.new(role: "tool", content: "Hello, world!", image_url: "https://example.com/image.jpg", tool_calls: [], tool_call_id: "123") }
+
+        it "returns a tool_hash with the image_url key" do
+          expect(message.to_hash).to eq({
+            role: "tool",
+            content: [
+              {type: "text", text: "Hello, world!"},
+              {type: "image_url", image_url: {url: "https://example.com/image.jpg"}}
+            ],
+            tool_call_id: "123"
+          })
+        end
+      end
     end
 
     context "when role is assistant" do