implement beta_content

libs/core/langchain_core/messages/ai.py

@@ -8,6 +8,7 @@ from typing import Any, Literal, Optional, Union, cast
 from pydantic import model_validator
 from typing_extensions import NotRequired, Self, TypedDict, override
 
+from langchain_core.messages import content_blocks as types
 from langchain_core.messages.base import (
     BaseMessage,
     BaseMessageChunk,
@@ -196,6 +197,79 @@ class AIMessage(BaseMessage):
             "invalid_tool_calls": self.invalid_tool_calls,
         }
 
+    @property
+    def beta_content(self) -> list[types.ContentBlock]:
+        """Return the content as a list of standard ContentBlocks.
+
+        To use this property, the corresponding chat model must support
+        ``output_version="v1"`` or higher:
+
+        .. code-block:: python
+
+            from langchain.chat_models import init_chat_model
+
+            llm = init_chat_model("...", output_version="v1")
+
+        otherwise, does best-effort parsing to standard types.
+        """
+        blocks: list[types.ContentBlock] = []
+        if isinstance(self.content, str):
+            if self.content:
+                blocks.append({"type": "text", "text": self.content})
+            else:
+                pass
+
+        elif isinstance(self.content, list):
+            for item in self.content:
+                if isinstance(item, str):
+                    blocks.append({"type": "text", "text": item})
+
+                elif isinstance(item, dict):
+                    item_type = item.get("type")
+                    if item_type == "text":
+                        blocks.append(cast("types.TextContentBlock", item))
+                    elif item_type == "tool_call":
+                        blocks.append(cast("types.ToolCallContentBlock", item))
+                    elif item_type == "reasoning":
+                        blocks.append(cast("types.ReasoningContentBlock", item))
+                    elif item_type == "non_standard":
+                        blocks.append(cast("types.NonStandardContentBlock", item))
+                    elif source_type := item.get("source_type"):
+                        if source_type == "url":
+                            blocks.append(cast("types.URLContentBlock", item))
+                        elif source_type == "base64":
+                            blocks.append(cast("types.Base64ContentBlock", item))
+                        elif source_type == "text":
+                            blocks.append(cast("types.PlainTextContentBlock", item))
+                        elif source_type == "id":
+                            blocks.append(cast("types.IDContentBlock", item))
+                        else:
+                            msg = f"Unknown source_type {source_type} in content block."
+                            raise ValueError(msg)
+                    else:
+                        msg = f"Unknown content block type {item_type}."
+                        raise ValueError(msg)
+                else:
+                    pass
+        else:
+            pass
+
+        # Add from tool_calls if missing from content
+        content_tool_call_ids = {
+            block.get("id")
+            for block in self.content
+            if isinstance(block, dict) and block.get("type") == "tool_call"
+        }
+        for tool_call in self.tool_calls:
+            if (id_ := tool_call.get("id")) and id_ not in content_tool_call_ids:
+                tool_call_block: types.ToolCallContentBlock = {
+                    "type": "tool_call",
+                    "id": id_,
+                }
+                blocks.append(tool_call_block)
+
+        return blocks
+
     # TODO: remove this logic if possible, reducing breaking nature of changes
     @model_validator(mode="before")
     @classmethod

libs/core/langchain_core/messages/base.py

@@ -7,7 +7,6 @@ from typing import TYPE_CHECKING, Any, Optional, Union, cast
 from pydantic import ConfigDict, Field
 
 from langchain_core.load.serializable import Serializable
-from langchain_core.messages import ContentBlock
 from langchain_core.utils import get_bolded_text
 from langchain_core.utils._merge import merge_dicts, merge_lists
 from langchain_core.utils.interactive_env import is_interactive_env
@@ -24,7 +23,7 @@ class BaseMessage(Serializable):
     Messages are the inputs and outputs of ChatModels.
     """
 
-    content: Union[str, list[Union[str, ContentBlock, dict]]]
+    content: Union[str, list[Union[str, dict]]]
     """The string contents of the message."""
 
     additional_kwargs: dict = Field(default_factory=dict)

libs/core/tests/unit_tests/messages/test_imports.py

@@ -6,21 +6,30 @@ EXPECTED_ALL = [
     "AIMessage",
     "AIMessageChunk",
     "AnyMessage",
+    "Base64ContentBlock",
     "BaseMessage",
     "BaseMessageChunk",
+    "ContentBlock",
     "ChatMessage",
     "ChatMessageChunk",
+    "DocumentCitation",
     "FunctionMessage",
     "FunctionMessageChunk",
     "HumanMessage",
     "HumanMessageChunk",
     "InvalidToolCall",
+    "NonStandardAnnotation",
+    "NonStandardContentBlock",
     "SystemMessage",
     "SystemMessageChunk",
+    "TextContentBlock",
     "ToolCall",
     "ToolCallChunk",
+    "ToolCallContentBlock",
     "ToolMessage",
     "ToolMessageChunk",
+    "UrlCitation",
+    "ReasoningContentBlock",
     "RemoveMessage",
     "convert_to_messages",
     "get_buffer_string",