fix: preserve image paths in fallback and session history

nanobot/agent/context.py

@@ -159,7 +159,11 @@ Reply directly with text for conversations. Only use the 'message' tool to send
             if not mime or not mime.startswith("image/"):
                 continue
             b64 = base64.b64encode(raw).decode()
-            images.append({"type": "image_url", "image_url": {"url": f"data:{mime};base64,{b64}"}})
+            images.append({
+                "type": "image_url",
+                "image_url": {"url": f"data:{mime};base64,{b64}"},
+                "_meta": {"path": str(p)},
+            })
 
         if not images:
             return text

nanobot/agent/loop.py

@@ -480,7 +480,9 @@ class AgentLoop:
                             continue  # Strip runtime context from multimodal messages
                         if (c.get("type") == "image_url"
                                 and c.get("image_url", {}).get("url", "").startswith("data:image/")):
-                            filtered.append({"type": "text", "text": "[image]"})
+                            path = (c.get("_meta") or {}).get("path", "")
+                            placeholder = f"[image: {path}]" if path else "[image]"
+                            filtered.append({"type": "text", "text": placeholder})
                         else:
                             filtered.append(c)
                     if not filtered:

nanobot/providers/base.py

@@ -89,14 +89,6 @@ class LLMProvider(ABC):
         "server error",
         "temporarily unavailable",
     )
-    _IMAGE_UNSUPPORTED_MARKERS = (
-        "image_url is only supported",
-        "does not support image",
-        "images are not supported",
-        "image input is not supported",
-        "image_url is not supported",
-        "unsupported image input",
-    )
 
     _SENTINEL = object()
 
@@ -107,11 +99,7 @@ class LLMProvider(ABC):
 
     @staticmethod
     def _sanitize_empty_content(messages: list[dict[str, Any]]) -> list[dict[str, Any]]:
-        """Replace empty text content that causes provider 400 errors.
+        """Sanitize message content: fix empty blocks, strip internal _meta fields."""
-
-        Empty content can appear when MCP tools return nothing. Most providers
-        reject empty-string content or empty text blocks in list content.
-        """
         result: list[dict[str, Any]] = []
         for msg in messages:
             content = msg.get("content")
@@ -123,18 +111,25 @@ class LLMProvider(ABC):
                 continue
 
             if isinstance(content, list):
-                filtered = [
+                new_items: list[Any] = []
-                    item for item in content
+                changed = False
-                    if not (
+                for item in content:
+                    if (
                         isinstance(item, dict)
                         and item.get("type") in ("text", "input_text", "output_text")
                         and not item.get("text")
-                    )
+                    ):
-                ]
+                        changed = True
-                if len(filtered) != len(content):
+                        continue
+                    if isinstance(item, dict) and "_meta" in item:
+                        new_items.append({k: v for k, v in item.items() if k != "_meta"})
+                        changed = True
+                    else:
+                        new_items.append(item)
+                if changed:
                     clean = dict(msg)
-                    if filtered:
+                    if new_items:
-                        clean["content"] = filtered
+                        clean["content"] = new_items
                     elif msg.get("role") == "assistant" and msg.get("tool_calls"):
                         clean["content"] = None
                     else:
@@ -197,11 +192,6 @@ class LLMProvider(ABC):
         err = (content or "").lower()
         return any(marker in err for marker in cls._TRANSIENT_ERROR_MARKERS)
 
-    @classmethod
-    def _is_image_unsupported_error(cls, content: str | None) -> bool:
-        err = (content or "").lower()
-        return any(marker in err for marker in cls._IMAGE_UNSUPPORTED_MARKERS)
-
     @staticmethod
     def _strip_image_content(messages: list[dict[str, Any]]) -> list[dict[str, Any]] | None:
         """Replace image_url blocks with text placeholder. Returns None if no images found."""
@@ -213,7 +203,9 @@ class LLMProvider(ABC):
                 new_content = []
                 for b in content:
                     if isinstance(b, dict) and b.get("type") == "image_url":
-                        new_content.append({"type": "text", "text": "[image omitted]"})
+                        path = (b.get("_meta") or {}).get("path", "")
+                        placeholder = f"[image: {path}]" if path else "[image omitted]"
+                        new_content.append({"type": "text", "text": placeholder})
                         found = True
                     else:
                         new_content.append(b)
@@ -267,11 +259,10 @@ class LLMProvider(ABC):
                 return response
 
             if not self._is_transient_error(response.content):
-                if self._is_image_unsupported_error(response.content):
+                stripped = self._strip_image_content(messages)
-                    stripped = self._strip_image_content(messages)
+                if stripped is not None:
-                    if stripped is not None:
+                    logger.warning("Non-transient LLM error with image content, retrying without images")
-                        logger.warning("Model does not support image input, retrying without images")
+                    return await self._safe_chat(**{**kw, "messages": stripped})
-                        return await self._safe_chat(**{**kw, "messages": stripped})
                 return response
 
             logger.warning(

tests/test_loop_save_turn.py

@@ -22,11 +22,30 @@ def test_save_turn_skips_multimodal_user_when_only_runtime_context() -> None:
     assert session.messages == []
 
 
-def test_save_turn_keeps_image_placeholder_after_runtime_strip() -> None:
+def test_save_turn_keeps_image_placeholder_with_path_after_runtime_strip() -> None:
     loop = _mk_loop()
     session = Session(key="test:image")
     runtime = ContextBuilder._RUNTIME_CONTEXT_TAG + "\nCurrent Time: now (UTC)"
 
+    loop._save_turn(
+        session,
+        [{
+            "role": "user",
+            "content": [
+                {"type": "text", "text": runtime},
+                {"type": "image_url", "image_url": {"url": "data:image/png;base64,abc"}, "_meta": {"path": "/media/feishu/photo.jpg"}},
+            ],
+        }],
+        skip=0,
+    )
+    assert session.messages[0]["content"] == [{"type": "text", "text": "[image: /media/feishu/photo.jpg]"}]
+
+
+def test_save_turn_keeps_image_placeholder_without_meta() -> None:
+    loop = _mk_loop()
+    session = Session(key="test:image-no-meta")
+    runtime = ContextBuilder._RUNTIME_CONTEXT_TAG + "\nCurrent Time: now (UTC)"
+
     loop._save_turn(
         session,
         [{

tests/test_provider_retry.py

@@ -126,10 +126,17 @@ async def test_chat_with_retry_explicit_override_beats_defaults() -> None:
 
 
 # ---------------------------------------------------------------------------
-# Image-unsupported fallback tests
+# Image fallback tests
 # ---------------------------------------------------------------------------
 
 _IMAGE_MSG = [
+    {"role": "user", "content": [
+        {"type": "text", "text": "describe this"},
+        {"type": "image_url", "image_url": {"url": "data:image/png;base64,abc"}, "_meta": {"path": "/media/test.png"}},
+    ]},
+]
+
+_IMAGE_MSG_NO_META = [
     {"role": "user", "content": [
         {"type": "text", "text": "describe this"},
         {"type": "image_url", "image_url": {"url": "data:image/png;base64,abc"}},
@@ -138,13 +145,10 @@ _IMAGE_MSG = [
 
 
 @pytest.mark.asyncio
-async def test_image_unsupported_error_retries_without_images() -> None:
+async def test_non_transient_error_with_images_retries_without_images() -> None:
-    """If the model rejects image_url, retry once with images stripped."""
+    """Any non-transient error retries once with images stripped when images are present."""
     provider = ScriptedProvider([
-        LLMResponse(
+        LLMResponse(content="API调用参数有误,请检查文档", finish_reason="error"),
-            content="Invalid content type. image_url is only supported by certain models",
-            finish_reason="error",
-        ),
         LLMResponse(content="ok, no image"),
     ])
 
@@ -157,17 +161,14 @@ async def test_image_unsupported_error_retries_without_images() -> None:
         content = msg.get("content")
         if isinstance(content, list):
             assert all(b.get("type") != "image_url" for b in content)
-            assert any("[image omitted]" in (b.get("text") or "") for b in content)
+            assert any("[image: /media/test.png]" in (b.get("text") or "") for b in content)
 
 
 @pytest.mark.asyncio
-async def test_image_unsupported_error_no_retry_without_image_content() -> None:
+async def test_non_transient_error_without_images_no_retry() -> None:
-    """If messages don't contain image_url blocks, don't retry on image error."""
+    """Non-transient errors without image content are returned immediately."""
     provider = ScriptedProvider([
-        LLMResponse(
+        LLMResponse(content="401 unauthorized", finish_reason="error"),
-            content="image_url is only supported by certain models",
-            finish_reason="error",
-        ),
     ])
 
     response = await provider.chat_with_retry(
@@ -179,31 +180,34 @@ async def test_image_unsupported_error_no_retry_without_image_content() -> None:
 
 
 @pytest.mark.asyncio
-async def test_image_unsupported_fallback_returns_error_on_second_failure() -> None:
+async def test_image_fallback_returns_error_on_second_failure() -> None:
     """If the image-stripped retry also fails, return that error."""
     provider = ScriptedProvider([
-        LLMResponse(
+        LLMResponse(content="some model error", finish_reason="error"),
-            content="does not support image input",
+        LLMResponse(content="still failing", finish_reason="error"),
-            finish_reason="error",
-        ),
-        LLMResponse(content="some other error", finish_reason="error"),
     ])
 
     response = await provider.chat_with_retry(messages=_IMAGE_MSG)
 
     assert provider.calls == 2
-    assert response.content == "some other error"
+    assert response.content == "still failing"
     assert response.finish_reason == "error"
 
 
 @pytest.mark.asyncio
-async def test_non_image_error_does_not_trigger_image_fallback() -> None:
+async def test_image_fallback_without_meta_uses_default_placeholder() -> None:
-    """Regular non-transient errors must not trigger image stripping."""
+    """When _meta is absent, fallback placeholder is '[image omitted]'."""
     provider = ScriptedProvider([
-        LLMResponse(content="401 unauthorized", finish_reason="error"),
+        LLMResponse(content="error", finish_reason="error"),
+        LLMResponse(content="ok"),
     ])
 
-    response = await provider.chat_with_retry(messages=_IMAGE_MSG)
+    response = await provider.chat_with_retry(messages=_IMAGE_MSG_NO_META)
 
-    assert provider.calls == 1
+    assert response.content == "ok"
-    assert response.content == "401 unauthorized"
+    assert provider.calls == 2
+    msgs_on_retry = provider.last_kwargs["messages"]
+    for msg in msgs_on_retry:
+        content = msg.get("content")
+        if isinstance(content, list):
+            assert any("[image omitted]" in (b.get("text") or "") for b in content)