From 77beafa6d3274510db71604fc963717cb6f04741 Mon Sep 17 00:00:00 2001
From: Guoguo <i@qwq.trade>
Date: Wed, 29 Apr 2026 19:02:14 -0700
Subject: [PATCH] fix(media): skip path tag append for JSON content (Feishu
 cards/posts)
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

When content is structured JSON (interactive cards, post messages),
injectPathTags now skips the fallback append — only placeholder
replacement is attempted. This prevents corrupting JSON payloads
like {"schema":"2.0",...} with appended [image:/path] tags.

Adds looksLikeJSON() helper and three test cases covering JSON
objects, arrays, and an end-to-end resolveMediaRefs scenario with
Feishu card content.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
---
 pkg/agent/agent_media.go | 14 ++++++++++++++
 pkg/agent/agent_test.go  | 41 ++++++++++++++++++++++++++++++++++++++++
 2 files changed, 55 insertions(+)

diff --git a/pkg/agent/agent_media.go b/pkg/agent/agent_media.go
index db9d5072b..9ec3ec585 100644
--- a/pkg/agent/agent_media.go
+++ b/pkg/agent/agent_media.go
@@ -242,7 +242,12 @@ func buildPathTag(mime, localPath string) string {
 // or appends if no matching generic tag is found. Channels emit a few different
 // placeholder formats — [image], [image: photo], [image: filename.jpg] — so we
 // match all of them via regex while leaving path tags ([image:/path]) untouched.
+//
+// When content is structured data (e.g., JSON from Feishu interactive cards or
+// post messages), tags are only injected via placeholder replacement — never
+// appended — to avoid corrupting the payload.
 func injectPathTags(content string, tags []string) string {
+	isStructured := looksLikeJSON(content)
 	for _, tag := range tags {
 		var pattern *regexp.Regexp
 		switch {
@@ -263,6 +268,10 @@ func injectPathTags(content string, tags []string) string {
 			}
 		}
 
+		if isStructured {
+			continue
+		}
+
 		if content == "" {
 			content = tag
 		} else {
@@ -271,3 +280,8 @@ func injectPathTags(content string, tags []string) string {
 	}
 	return content
 }
+
+func looksLikeJSON(s string) bool {
+	s = strings.TrimSpace(s)
+	return len(s) > 1 && (s[0] == '{' || s[0] == '[')
+}
diff --git a/pkg/agent/agent_test.go b/pkg/agent/agent_test.go
index 26da280e1..e1ee0fafb 100644
--- a/pkg/agent/agent_test.go
+++ b/pkg/agent/agent_test.go
@@ -5040,6 +5040,47 @@ func TestInjectPathTags_DoesNotReplacePathTag(t *testing.T) {
 	}
 }
 
+func TestInjectPathTags_SkipsAppendForJSONContent(t *testing.T) {
+	jsonContent := `{"schema":"2.0","body":{"elements":[{"tag":"img","img_key":"img_123"}]}}`
+	got := injectPathTags(jsonContent, []string{"[image:/tmp/photo.png]"})
+	if got != jsonContent {
+		t.Fatalf("expected JSON content unchanged, got %q", got)
+	}
+}
+
+func TestInjectPathTags_JSONArrayContent(t *testing.T) {
+	jsonContent := `[{"tag":"text","text":"hello"}]`
+	got := injectPathTags(jsonContent, []string{"[file:/tmp/doc.pdf]"})
+	if got != jsonContent {
+		t.Fatalf("expected JSON array content unchanged, got %q", got)
+	}
+}
+
+func TestResolveMediaRefs_JSONContentPreservesStructure(t *testing.T) {
+	store := media.NewFileMediaStore()
+	dir := t.TempDir()
+
+	pngPath := filepath.Join(dir, "card_img.png")
+	pngHeader := []byte{
+		0x89, 0x50, 0x4E, 0x47, 0x0D, 0x0A, 0x1A, 0x0A,
+		0x00, 0x00, 0x00, 0x0D, 0x49, 0x48, 0x44, 0x52,
+		0x00, 0x00, 0x00, 0x01, 0x00, 0x00, 0x00, 0x01, 0x08, 0x02,
+		0x00, 0x00, 0x00, 0x90, 0x77, 0x53, 0xDE,
+	}
+	os.WriteFile(pngPath, pngHeader, 0o644)
+	ref, _ := store.Store(pngPath, media.MediaMeta{ContentType: "image/png"}, "test")
+
+	jsonContent := `{"schema":"2.0","body":{"elements":[{"tag":"img","img_key":"img_123"}]}}`
+	messages := []providers.Message{
+		{Role: "user", Content: jsonContent, Media: []string{ref}},
+	}
+	result := resolveMediaRefs(messages, store, config.DefaultMaxMediaSize)
+
+	if result[0].Content != jsonContent {
+		t.Fatalf("expected JSON content preserved, got %q", result[0].Content)
+	}
+}
+
 func TestResolveMediaRefs_EmptyContentGetsPathTag(t *testing.T) {
 	store := media.NewFileMediaStore()
 	dir := t.TempDir()