diff --git a/internal/backend/agent/bridge/exec/bridge_read_image_test.go b/internal/backend/agent/bridge/exec/bridge_read_image_test.go
new file mode 100644
index 0000000..966eca1
--- /dev/null
+++ b/internal/backend/agent/bridge/exec/bridge_read_image_test.go
@@ -0,0 +1,54 @@
+package execbridge
+
+import (
+	"bytes"
+	"strings"
+	"testing"
+
+	"cursor/gen/agentv1"
+)
+
+func TestConvertReadResultPreservesLargeImagesOnly(t *testing.T) {
+	largePNG := append([]byte("\x89PNG\r\n\x1a\n"), bytes.Repeat([]byte{0}, readReplayBinaryLimit)...)
+	imageResult := convertReadResultToReadToolResult(&agentv1.ReadResult{
+		Result: &agentv1.ReadResult_Success{
+			Success: &agentv1.ReadSuccess{
+				Path:   "image.png",
+				Output: &agentv1.ReadSuccess_Data{Data: largePNG},
+			},
+		},
+	})
+	imageSuccess := imageResult.GetSuccess()
+	if imageSuccess == nil {
+		t.Fatal("large image result is not successful")
+	}
+	if !bytes.Equal(imageSuccess.GetData(), largePNG) {
+		t.Fatalf("large image data bytes = %d, want %d", len(imageSuccess.GetData()), len(largePNG))
+	}
+	if imageSuccess.GetExceededLimit() {
+		t.Fatal("large image unexpectedly marked as exceeded limit")
+	}
+
+	largeBinary := bytes.Repeat([]byte{0xff}, readReplayBinaryLimit+1)
+	binaryResult := convertReadResultToReadToolResult(&agentv1.ReadResult{
+		Result: &agentv1.ReadResult_Success{
+			Success: &agentv1.ReadSuccess{
+				Path:   "archive.bin",
+				Output: &agentv1.ReadSuccess_Data{Data: largeBinary},
+			},
+		},
+	})
+	binarySuccess := binaryResult.GetSuccess()
+	if binarySuccess == nil {
+		t.Fatal("large binary result is not successful")
+	}
+	if !binarySuccess.GetExceededLimit() {
+		t.Fatal("large non-image binary was not marked as exceeded limit")
+	}
+	if binarySuccess.GetData() != nil {
+		t.Fatal("large non-image binary data was retained")
+	}
+	if !strings.Contains(binarySuccess.GetContent(), "Read binary data") {
+		t.Fatalf("large binary fallback = %q", binarySuccess.GetContent())
+	}
+}
diff --git a/internal/backend/agent/model/tool_image_test.go b/internal/backend/agent/model/tool_image_test.go
new file mode 100644
index 0000000..36ab108
--- /dev/null
+++ b/internal/backend/agent/model/tool_image_test.go
@@ -0,0 +1,86 @@
+package modeladapter
+
+import (
+	"strings"
+	"testing"
+)
+
+func TestToolImageProviderEncodings(t *testing.T) {
+	message := toolImageMessageForTest()
+
+	t.Run("openai_chat", func(t *testing.T) {
+		items, err := normalizeOpenAIProviderMessages([]Message{message}, false)
+		if err != nil {
+			t.Fatalf("normalizeOpenAIProviderMessages() error = %v", err)
+		}
+		if len(items) != 1 || items[0]["role"] != "tool" || items[0]["tool_call_id"] != "call-1" {
+			t.Fatalf("openai chat tool message = %#v", items)
+		}
+		content, ok := items[0]["content"].([]map[string]any)
+		if !ok || len(content) != 2 {
+			t.Fatalf("openai chat content = %#v", items[0]["content"])
+		}
+		imageURL, ok := content[1]["image_url"].(map[string]any)
+		if content[1]["type"] != "image_url" || !ok || !strings.HasPrefix(imageURL["url"].(string), "data:image/png;base64,") {
+			t.Fatalf("openai chat image part = %#v", content[1])
+		}
+	})
+
+	t.Run("openai_responses", func(t *testing.T) {
+		_, items, err := normalizeOpenAIResponsesInput([]Message{message})
+		if err != nil {
+			t.Fatalf("normalizeOpenAIResponsesInput() error = %v", err)
+		}
+		if len(items) != 1 || items[0]["type"] != "function_call_output" {
+			t.Fatalf("openai responses items = %#v", items)
+		}
+		content, ok := items[0]["output"].([]map[string]any)
+		if !ok || len(content) != 2 {
+			t.Fatalf("openai responses output = %#v", items[0]["output"])
+		}
+		if content[0]["type"] != "input_text" || content[1]["type"] != "input_image" {
+			t.Fatalf("openai responses content = %#v", content)
+		}
+	})
+
+	t.Run("anthropic", func(t *testing.T) {
+		_, messages, err := normalizeAnthropicProviderMessages([]Message{message}, false, false)
+		if err != nil {
+			t.Fatalf("normalizeAnthropicProviderMessages() error = %v", err)
+		}
+		if len(messages) != 1 || messages[0].Role != "user" || len(messages[0].Content) != 1 {
+			t.Fatalf("anthropic messages = %#v", messages)
+		}
+		toolResult := messages[0].Content[0]
+		if toolResult["type"] != "tool_result" || toolResult["tool_use_id"] != "call-1" {
+			t.Fatalf("anthropic tool result = %#v", toolResult)
+		}
+		content, ok := toolResult["content"].([]map[string]any)
+		if !ok || len(content) != 2 {
+			t.Fatalf("anthropic tool content = %#v", toolResult["content"])
+		}
+		if content[0]["type"] != "text" || content[1]["type"] != "image" {
+			t.Fatalf("anthropic content blocks = %#v", content)
+		}
+	})
+}
+
+func toolImageMessageForTest() Message {
+	return Message{
+		Role:       "tool",
+		Content:    "read binary bytes=16",
+		ToolCallID: "call-1",
+		Name:       "Read",
+		ContentParts: []ContentPart{
+			{Type: "text", Text: "read binary bytes=16"},
+			{
+				Type: "image",
+				Image: &ImageContent{
+					MIMEType: "image/png",
+					Path:     "diagram.png",
+					Data:     []byte("\x89PNG\r\n\x1a\nimage"),
+				},
+			},
+		},
+	}
+}
diff --git a/internal/backend/forwarder/projector_read_image_test.go b/internal/backend/forwarder/projector_read_image_test.go
new file mode 100644
index 0000000..5f9d7e4
--- /dev/null
+++ b/internal/backend/forwarder/projector_read_image_test.go
@@ -0,0 +1,99 @@
+package forwarder
+
+import (
+	"bytes"
+	"fmt"
+	"strings"
+	"testing"
+
+	"google.golang.org/protobuf/encoding/protojson"
+
+	"cursor/gen/agentv1"
+)
+
+func TestProjectPromptReplayAttachesReadImageToToolMessage(t *testing.T) {
+	testCases := []struct {
+		name        string
+		imageData   []byte
+		fileSize    uint32
+		wantSummary string
+	}{
+		{
+			name:        "small image omits result json base64",
+			imageData:   append([]byte("\x89PNG\r\n\x1a\n"), bytes.Repeat([]byte{0}, 64)...),
+			fileSize:    391998,
+			wantSummary: `read image path="diagram.png" mime=image/png bytes=72 file_size=391998`,
+		},
+		{
+			name:        "large image omits replay truncation notice",
+			imageData:   append([]byte("\x89PNG\r\n\x1a\n"), bytes.Repeat([]byte{0}, projectedReadReplayLimit)...),
+			fileSize:    uint32(projectedReadReplayLimit + 8),
+			wantSummary: fmt.Sprintf(`read image path="diagram.png" mime=image/png bytes=%d`, projectedReadReplayLimit+8),
+		},
+	}
+
+	for _, testCase := range testCases {
+		t.Run(testCase.name, func(t *testing.T) {
+			toolCall := &agentv1.ToolCall{
+				Tool: &agentv1.ToolCall_ReadToolCall{
+					ReadToolCall: &agentv1.ReadToolCall{
+						Args: &agentv1.ReadToolArgs{Path: "diagram.png"},
+						Result: &agentv1.ReadToolResult{
+							Result: &agentv1.ReadToolResult_Success{
+								Success: &agentv1.ReadToolSuccess{
+									FileSize: testCase.fileSize,
+									Path:     "diagram.png",
+									Output:   &agentv1.ReadToolSuccess_Data{Data: testCase.imageData},
+								},
+							},
+						},
+					},
+				},
+			}
+			encodedToolCall, err := protojson.Marshal(toolCall)
+			if err != nil {
+				t.Fatalf("marshal read tool call: %v", err)
+			}
+			conversation := &ConversationFile{
+				ConversationID: "conversation-1",
+				NextTurnSeq:    2,
+				Entries: []HistoryEntry{
+					newToolResultEntry(1, "request-1", "call-1", "Read", `{"path":"diagram.png"}`, fmt.Sprintf("read binary bytes=%d", len(testCase.imageData)), "", encodedToolCall),
+				},
+			}
+
+			messages, err := NewHistoryProjector().ProjectPromptReplay(conversation)
+			if err != nil {
+				t.Fatalf("ProjectPromptReplay() error = %v", err)
+			}
+			if len(messages) != 2 {
+				t.Fatalf("message count = %d, want assistant tool call and tool result", len(messages))
+			}
+			toolMessage := messages[1]
+			if toolMessage.Role != "tool" || toolMessage.ToolCallID != "call-1" || toolMessage.Name != "Read" {
+				t.Fatalf("tool message metadata = %#v", toolMessage)
+			}
+			if toolMessage.Content != testCase.wantSummary {
+				t.Fatalf("tool content = %q, want %q", toolMessage.Content, testCase.wantSummary)
+			}
+			for _, forbidden := range []string{`"data"`, "iVBOR", "base64", "tool result replay truncated"} {
+				if strings.Contains(toolMessage.Content, forbidden) {
+					t.Fatalf("tool content contains %q: %q", forbidden, toolMessage.Content)
+				}
+			}
+			if len(toolMessage.ContentParts) != 2 {
+				t.Fatalf("tool content parts = %d, want text and image", len(toolMessage.ContentParts))
+			}
+			if toolMessage.ContentParts[0].Type != "text" || toolMessage.ContentParts[0].Text != testCase.wantSummary {
+				t.Fatalf("tool text part = %#v", toolMessage.ContentParts[0])
+			}
+			image := toolMessage.ContentParts[1].Image
+			if toolMessage.ContentParts[1].Type != "image" || image == nil {
+				t.Fatalf("tool image part = %#v", toolMessage.ContentParts[1])
+			}
+			if image.MIMEType != "image/png" || image.Path != "diagram.png" || !bytes.Equal(image.Data, testCase.imageData) {
+				t.Fatalf("tool image = %#v", image)
+			}
+		})
+	}
+}