diff --git a/pkg/agent/context.go b/pkg/agent/context.go
index 8868d6bf4..6fccbaf53 100644
--- a/pkg/agent/context.go
+++ b/pkg/agent/context.go
@@ -465,11 +465,10 @@ func (cb *ContextBuilder) BuildMessages(
 	messages = append(messages, history...)
 
 	// Add current user message
-	if strings.TrimSpace(currentMessage) != "" || len(media) > 0 {
+	if strings.TrimSpace(currentMessage) != "" {
 		messages = append(messages, providers.Message{
 			Role:    "user",
 			Content: currentMessage,
-			Media:   media,
 		})
 	}
 
diff --git a/pkg/agent/loop.go b/pkg/agent/loop.go
index 29c39d396..88afa6119 100644
--- a/pkg/agent/loop.go
+++ b/pkg/agent/loop.go
@@ -8,11 +8,9 @@ package agent
 
 import (
 	"context"
-	"encoding/base64"
 	"encoding/json"
 	"errors"
 	"fmt"
-	"os"
 	"path/filepath"
 	"strings"
 	"sync"
@@ -49,12 +47,11 @@ type AgentLoop struct {
 
 // processOptions configures how a message is processed
 type processOptions struct {
-	SessionKey      string   // Session identifier for history/context
-	Channel         string   // Target channel for tool execution
-	ChatID          string   // Target chat ID for tool execution
-	UserMessage     string   // User message content (may include prefix)
-	Media           []string // Media URLs attached to the user message
-	DefaultResponse string   // Response when LLM returns empty
+	SessionKey      string // Session identifier for history/context
+	Channel         string // Target channel for tool execution
+	ChatID          string // Target chat ID for tool execution
+	UserMessage     string // User message content (may include prefix)
+	DefaultResponse string // Response when LLM returns empty
 	EnableSummary   bool   // Whether to trigger summarization
 	SendResponse    bool   // Whether to send response via bus
 	NoHistory       bool   // If true, don't load session history (for heartbeat)
@@ -499,7 +496,6 @@ func (al *AgentLoop) processMessage(ctx context.Context, msg bus.InboundMessage)
 		Channel:         msg.Channel,
 		ChatID:          msg.ChatID,
 		UserMessage:     msg.Content,
-		Media:           msg.Media,
 		DefaultResponse: defaultResponse,
 		EnableSummary:   true,
 		SendResponse:    false,
@@ -606,11 +602,10 @@ func (al *AgentLoop) runAgentLoop(
 		history,
 		summary,
 		opts.UserMessage,
-		opts.Media,
+		nil,
 		opts.Channel,
 		opts.ChatID,
 	)
-	messages = resolveMediaRefs(messages, al.mediaStore)
 
 	// 3. Save user message to session
 	agent.Sessions.AddMessage(opts.SessionKey, "user", opts.UserMessage)
@@ -1481,105 +1476,3 @@ func extractParentPeer(msg bus.InboundMessage) *routing.RoutePeer {
 	}
 	return &routing.RoutePeer{Kind: parentKind, ID: parentID}
 }
-
-// maxMediaFileSize is the maximum file size (20 MB) for media resolution.
-// Files larger than this are skipped to prevent OOM under concurrent load.
-const maxMediaFileSize = 20 * 1024 * 1024
-
-// resolveMediaRefs replaces media:// refs in message Media fields with base64 data URLs.
-// Returns a new slice with resolved URLs; original messages are not mutated.
-func resolveMediaRefs(messages []providers.Message, store media.MediaStore) []providers.Message {
-	if store == nil {
-		return messages
-	}
-
-	result := make([]providers.Message, len(messages))
-	copy(result, messages)
-
-	for i, m := range result {
-		if len(m.Media) == 0 {
-			continue
-		}
-
-		resolved := make([]string, 0, len(m.Media))
-		for _, ref := range m.Media {
-			if !strings.HasPrefix(ref, "media://") {
-				resolved = append(resolved, ref)
-				continue
-			}
-
-			localPath, meta, err := store.ResolveWithMeta(ref)
-			if err != nil {
-				logger.WarnCF("agent", "Failed to resolve media ref", map[string]any{
-					"ref":   ref,
-					"error": err.Error(),
-				})
-				continue
-			}
-
-			info, err := os.Stat(localPath)
-			if err != nil {
-				logger.WarnCF("agent", "Failed to stat media file", map[string]any{
-					"path":  localPath,
-					"error": err.Error(),
-				})
-				continue
-			}
-			if info.Size() > maxMediaFileSize {
-				logger.WarnCF("agent", "Media file too large, skipping", map[string]any{
-					"path":     localPath,
-					"size":     info.Size(),
-					"max_size": maxMediaFileSize,
-				})
-				continue
-			}
-
-			data, err := os.ReadFile(localPath)
-			if err != nil {
-				logger.WarnCF("agent", "Failed to read media file", map[string]any{
-					"path":  localPath,
-					"error": err.Error(),
-				})
-				continue
-			}
-
-			mime := meta.ContentType
-			if mime == "" {
-				mime = mimeFromExtension(filepath.Ext(localPath))
-			}
-			if mime == "" {
-				logger.WarnCF("agent", "Unknown media type, skipping", map[string]any{
-					"path": localPath,
-					"ext":  filepath.Ext(localPath),
-				})
-				continue
-			}
-
-			dataURL := "data:" + mime + ";base64," + base64.StdEncoding.EncodeToString(data)
-			resolved = append(resolved, dataURL)
-		}
-
-		result[i].Media = resolved
-	}
-
-	return result
-}
-
-// mimeFromExtension returns a MIME type for common image extensions.
-// Returns empty string for unrecognized extensions.
-func mimeFromExtension(ext string) string {
-	switch strings.ToLower(ext) {
-	case ".jpg", ".jpeg":
-		return "image/jpeg"
-	case ".png":
-		return "image/png"
-	case ".gif":
-		return "image/gif"
-	case ".webp":
-		return "image/webp"
-	case ".bmp":
-		return "image/bmp"
-	default:
-		return ""
-	}
-}
diff --git a/pkg/agent/loop_test.go b/pkg/agent/loop_test.go
index 4c803fea6..3565314fe 100644
--- a/pkg/agent/loop_test.go
+++ b/pkg/agent/loop_test.go
@@ -6,14 +6,12 @@ import (
 	"os"
 	"path/filepath"
 	"slices"
-	"strings"
 	"testing"
 	"time"
 
 	"github.com/sipeed/picoclaw/pkg/bus"
 	"github.com/sipeed/picoclaw/pkg/channels"
 	"github.com/sipeed/picoclaw/pkg/config"
-	"github.com/sipeed/picoclaw/pkg/media"
 	"github.com/sipeed/picoclaw/pkg/providers"
 	"github.com/sipeed/picoclaw/pkg/tools"
 )
@@ -810,124 +808,3 @@ func TestHandleReasoning(t *testing.T) {
 		}
 	})
 }
-
-func TestMimeFromExtension(t *testing.T) {
-	tests := []struct {
-		ext  string
-		want string
-	}{
-		{".jpg", "image/jpeg"},
-		{".JPEG", "image/jpeg"},
-		{".png", "image/png"},
-		{".gif", "image/gif"},
-		{".webp", "image/webp"},
-		{".bmp", "image/bmp"},
-		{".txt", ""},
-		{".pdf", ""},
-		{"", ""},
-	}
-	for _, tt := range tests {
-		if got := mimeFromExtension(tt.ext); got != tt.want {
-			t.Errorf("mimeFromExtension(%q) = %q, want %q", tt.ext, got, tt.want)
-		}
-	}
-}
-
-func TestResolveMediaRefs_NilStore(t *testing.T) {
-	msgs := []providers.Message{{Role: "user", Content: "hi", Media: []string{"media://abc"}}}
-	result := resolveMediaRefs(msgs, nil)
-	if result[0].Media[0] != "media://abc" {
-		t.Error("nil store should return messages unchanged")
-	}
-}
-
-func TestResolveMediaRefs_NonMediaRef(t *testing.T) {
-	msgs := []providers.Message{{Role: "user", Content: "hi", Media: []string{"https://example.com/img.png"}}}
-	result := resolveMediaRefs(msgs, media.NewFileMediaStore())
-	if result[0].Media[0] != "https://example.com/img.png" {
-		t.Error("non-media:// refs should be passed through unchanged")
-	}
-}
-
-func TestResolveMediaRefs_ResolvesToBase64(t *testing.T) {
-	store := media.NewFileMediaStore()
-
-	imgPath := filepath.Join(t.TempDir(), "test.png")
-	if err := os.WriteFile(imgPath, []byte("fake-png-data"), 0o644); err != nil {
-		t.Fatal(err)
-	}
-
-	ref, err := store.Store(imgPath, media.MediaMeta{ContentType: "image/png"}, "test")
-	if err != nil {
-		t.Fatal(err)
-	}
-
-	msgs := []providers.Message{{Role: "user", Content: "describe", Media: []string{ref}}}
-	result := resolveMediaRefs(msgs, store)
-
-	if len(result[0].Media) != 1 {
-		t.Fatalf("expected 1 resolved media, got %d", len(result[0].Media))
-	}
-	if !strings.HasPrefix(result[0].Media[0], "data:image/png;base64,") {
-		t.Errorf("expected data URL, got %s", result[0].Media[0][:40])
-	}
-}
-
-func TestResolveMediaRefs_SkipsOversizedFile(t *testing.T) {
-	store := media.NewFileMediaStore()
-
-	bigPath := filepath.Join(t.TempDir(), "big.jpg")
-	if err := os.WriteFile(bigPath, make([]byte, maxMediaFileSize+1), 0o644); err != nil {
-		t.Fatal(err)
-	}
-
-	ref, err := store.Store(bigPath, media.MediaMeta{ContentType: "image/jpeg"}, "test")
-	if err != nil {
-		t.Fatal(err)
-	}
-
-	msgs := []providers.Message{{Role: "user", Content: "hi", Media: []string{ref}}}
-	result := resolveMediaRefs(msgs, store)
-
-	if len(result[0].Media) != 0 {
-		t.Error("oversized file should be skipped")
-	}
-}
-
-func TestResolveMediaRefs_SkipsUnknownExtension(t *testing.T) {
-	store := media.NewFileMediaStore()
-
-	txtPath := filepath.Join(t.TempDir(), "readme.txt")
-	if err := os.WriteFile(txtPath, []byte("hello"), 0o644); err != nil {
-		t.Fatal(err)
-	}
-
-	ref, err := store.Store(txtPath, media.MediaMeta{}, "test")
-	if err != nil {
-		t.Fatal(err)
-	}
-
-	msgs := []providers.Message{{Role: "user", Content: "hi", Media: []string{ref}}}
-	result := resolveMediaRefs(msgs, store)
-
-	if len(result[0].Media) != 0 {
-		t.Error("unknown extension with no ContentType should be skipped")
-	}
-}
-
-func TestResolveMediaRefs_DoesNotMutateOriginal(t *testing.T) {
-	store := media.NewFileMediaStore()
-
-	imgPath := filepath.Join(t.TempDir(), "test.jpg")
-	if err := os.WriteFile(imgPath, []byte("data"), 0o644); err != nil {
-		t.Fatal(err)
-	}
-
-	ref, _ := store.Store(imgPath, media.MediaMeta{ContentType: "image/jpeg"}, "test")
-	original := []providers.Message{{Role: "user", Content: "hi", Media: []string{ref}}}
-	resolveMediaRefs(original, store)
-
-	if !strings.HasPrefix(original[0].Media[0], "media://") {
-		t.Error("original message should not be mutated")
-	}
-}
diff --git a/pkg/providers/openai_compat/provider.go b/pkg/providers/openai_compat/provider.go
index e3cd1560e..3a18b8b16 100644
--- a/pkg/providers/openai_compat/provider.go
+++ b/pkg/providers/openai_compat/provider.go
@@ -116,7 +116,7 @@ func (p *Provider) Chat(
 
 	requestBody := map[string]any{
 		"model":    model,
-		"messages": serializeMessages(messages),
+		"messages": stripSystemParts(messages),
 	}
 
 	if len(tools) > 0 {
@@ -195,60 +195,6 @@ func (p *Provider) Chat(
 	return parseResponse(body)
 }
 
-func serializeMessages(messages []Message) []map[string]interface{} {
-	result := make([]map[string]interface{}, 0, len(messages))
-	for _, m := range messages {
-		if len(m.Media) == 0 {
-			msg := map[string]interface{}{
-				"role":    m.Role,
-				"content": m.Content,
-			}
-			if m.ToolCallID != "" {
-				msg["tool_call_id"] = m.ToolCallID
-			}
-			if len(m.ToolCalls) > 0 {
-				msg["tool_calls"] = m.ToolCalls
-			}
-			if m.ReasoningContent != "" {
-				msg["reasoning_content"] = m.ReasoningContent
-			}
-			result = append(result, msg)
-			continue
-		}
-
-		parts := make([]map[string]interface{}, 0, 1+len(m.Media))
-		if m.Content != "" {
-			parts = append(parts, map[string]interface{}{
-				"type": "text",
-				"text": m.Content,
-			})
-		}
-		for _, mediaURL := range m.Media {
-			parts = append(parts, map[string]interface{}{
-				"type": "image_url",
-				"image_url": map[string]interface{}{
-					"url": mediaURL,
-				},
-			})
-		}
-		msg := map[string]interface{}{
-			"role":    m.Role,
-			"content": parts,
-		}
-		if m.ToolCallID != "" {
-			msg["tool_call_id"] = m.ToolCallID
-		}
-		if len(m.ToolCalls) > 0 {
-			msg["tool_calls"] = m.ToolCalls
-		}
-		if m.ReasoningContent != "" {
-			msg["reasoning_content"] = m.ReasoningContent
-		}
-		result = append(result, msg)
-	}
-	return result
-}
-
 func parseResponse(body []byte) (*LLMResponse, error) {
 	var apiResponse struct {
 		Choices []struct {
diff --git a/pkg/providers/openai_compat/provider_test.go b/pkg/providers/openai_compat/provider_test.go
index 0fd912541..53b9e75ee 100644
--- a/pkg/providers/openai_compat/provider_test.go
+++ b/pkg/providers/openai_compat/provider_test.go
@@ -416,73 +416,3 @@ func TestProvider_FunctionalOptionRequestTimeoutNonPositive(t *testing.T) {
 		t.Fatalf("http timeout = %v, want %v", p.httpClient.Timeout, defaultRequestTimeout)
 	}
 }
-
-func TestSerializeMessages_PlainText(t *testing.T) {
-	msgs := []Message{
-		{Role: "user", Content: "hello"},
-		{Role: "assistant", Content: "hi"},
-	}
-	result := serializeMessages(msgs)
-	if len(result) != 2 {
-		t.Fatalf("expected 2 messages, got %d", len(result))
-	}
-	if result[0]["content"] != "hello" {
-		t.Errorf("expected plain string content, got %v", result[0]["content"])
-	}
-}
-
-func TestSerializeMessages_WithMedia(t *testing.T) {
-	msgs := []Message{
-		{Role: "user", Content: "describe this", Media: []string{"data:image/png;base64,abc123"}},
-	}
-	result := serializeMessages(msgs)
-	if len(result) != 1 {
-		t.Fatalf("expected 1 message, got %d", len(result))
-	}
-	parts, ok := result[0]["content"].([]map[string]interface{})
-	if !ok {
-		t.Fatalf("expected content to be []map, got %T", result[0]["content"])
-	}
-	if len(parts) != 2 {
-		t.Fatalf("expected 2 parts (text + image), got %d", len(parts))
-	}
-	if parts[0]["type"] != "text" {
-		t.Errorf("expected first part type=text, got %v", parts[0]["type"])
-	}
-	if parts[1]["type"] != "image_url" {
-		t.Errorf("expected second part type=image_url, got %v", parts[1]["type"])
-	}
-}
-
-func TestSerializeMessages_WithMediaPreservesToolFields(t *testing.T) {
-	msgs := []Message{
-		{
-			Role:             "assistant",
-			Content:          "result",
-			Media:            []string{"data:image/png;base64,abc"},
-			ToolCallID:       "call_123",
-			ToolCalls:        []ToolCall{{ID: "tc_1", Type: "function", Function: &FunctionCall{Name: "test", Arguments: "{}"}}},
-			ReasoningContent: "thinking...",
-		},
-	}
-	result := serializeMessages(msgs)
-	if result[0]["tool_call_id"] != "call_123" {
-		t.Errorf("expected tool_call_id=call_123, got %v", result[0]["tool_call_id"])
-	}
-	if result[0]["tool_calls"] == nil {
-		t.Error("expected tool_calls to be present")
-	}
-	if result[0]["reasoning_content"] != "thinking..." {
-		t.Errorf("expected reasoning_content, got %v", result[0]["reasoning_content"])
-	}
-}
-
-func TestSerializeMessages_EmptyMediaUsesPlainFormat(t *testing.T) {
-	msgs := []Message{
-		{Role: "user", Content: "hello", Media: []string{}},
-	}
-	result := serializeMessages(msgs)
-	if _, ok := result[0]["content"].(string); !ok {
-		t.Errorf("empty Media should use plain string format, got %T", result[0]["content"])
-	}
-}
diff --git a/pkg/providers/protocoltypes/types.go b/pkg/providers/protocoltypes/types.go
index efac1e10b..99f13334e 100644
--- a/pkg/providers/protocoltypes/types.go
+++ b/pkg/providers/protocoltypes/types.go
@@ -65,7 +65,6 @@ type ContentBlock struct {
 type Message struct {
 	Role             string         `json:"role"`
 	Content          string         `json:"content"`
-	Media            []string       `json:"media,omitempty"` // URLs of images or other media attachments
 	ReasoningContent string         `json:"reasoning_content,omitempty"`
 	SystemParts      []ContentBlock `json:"system_parts,omitempty"` // structured system blocks for cache-aware adapters
 	ToolCalls        []ToolCall     `json:"tool_calls,omitempty"`