beeai-reasoning.patch

diff --git a/python/beeai_framework/adapters/litellm/chat.py b/python/beeai_framework/adapters/litellm/chat.py
index b5c5a9b4..9ad9f544 100644
--- a/python/beeai_framework/adapters/litellm/chat.py
+++ b/python/beeai_framework/adapters/litellm/chat.py
@@ -37,7 +37,10 @@ from beeai_framework.backend.chat import (
 )
 from beeai_framework.backend.errors import ChatModelError
 from beeai_framework.backend.message import (
+    AnyMessage,
     AssistantMessage,
+    AssistantMessageContent,
+    MessageReasoningContent,
     MessageTextContent,
     MessageToolCallContent,
     ToolMessage,
@@ -195,6 +198,7 @@ class LiteLLMChatModel(ChatModel, ABC):
                         "role": "assistant",
                         "content": msg_text_content or None,
                         "tool_calls": msg_tool_calls or None,
+                        "thinking_blocks": message.meta.get("thinking_blocks"),
                     }
                     if self.model_supports_tool_calling
                     else {
@@ -307,27 +311,41 @@ class LiteLLMChatModel(ChatModel, ABC):
                     total_cost_usd=prompt_tokens_cost_usd + completion_tokens_cost_usd,
                 )
 
-        return ChatModelOutput(
-            output=(
-                [
-                    AssistantMessage(
-                        [
-                            MessageToolCallContent(
-                                id=call.id or "",
-                                tool_name=call.function.name or "",
-                                args=call.function.arguments,
-                            )
-                            for call in update.tool_calls
-                        ],
-                        id=chunk.id,
+        reasoning_content = getattr(update, "reasoning_content", None) if update else None
+        # Anthropic requires `thinking_blocks` (with cryptographic signatures) to be sent back
+        # in conversation history; without them LiteLLM silently disables thinking on follow-up turns
+        meta = None
+        if (thinking_blocks := (getattr(update, "thinking_blocks", None) if update else None)) and (
+            # Streaming deltas carry partial blocks without signatures - filter those out
+            signed_thinking_blocks := [
+                b
+                for b in thinking_blocks
+                if (b.get("signature") if isinstance(b, dict) else getattr(b, "signature", None))
+            ]
+        ):
+            meta = {"thinking_blocks": signed_thinking_blocks}
+
+        if update:
+            parts: list[AssistantMessageContent] = []
+            if reasoning_content:
+                parts.append(MessageReasoningContent(text=reasoning_content))
+            if update.tool_calls:
+                parts.extend(
+                    MessageToolCallContent(
+                        id=call.id or "",
+                        tool_name=call.function.name or "",
+                        args=call.function.arguments,
                     )
-                    if update.tool_calls
-                    # pyrefly: ignore [bad-argument-type]
-                    else AssistantMessage(update.content or update.reasoning_content or "", id=chunk.id)
-                ]
-                if (update and update.model_dump(exclude_none=True))
-                else []
-            ),
+                    for call in update.tool_calls
+                )
+            if update.content:
+                parts.append(MessageTextContent(text=update.content))
+            output: list[AnyMessage] = [AssistantMessage(parts, id=chunk.id, meta=meta)] if parts or meta else []
+        else:
+            output: list[AnyMessage] = []
+
+        return ChatModelOutput(
+            output=output,
             # Will be set later
             output_structured=None,
             finish_reason=finish_reason,
diff --git a/python/beeai_framework/backend/__init__.py b/python/beeai_framework/backend/__init__.py
index fe8e5002..f3d7fe86 100644
--- a/python/beeai_framework/backend/__init__.py
+++ b/python/beeai_framework/backend/__init__.py
@@ -23,6 +23,7 @@ from beeai_framework.backend.message import (
     Message,
     MessageFileContent,
     MessageImageContent,
+    MessageReasoningContent,
     MessageTextContent,
     MessageToolCallContent,
     MessageToolResultContent,
@@ -65,6 +66,7 @@ __all__ = [
     "MessageError",
     "MessageFileContent",
     "MessageImageContent",
+    "MessageReasoningContent",
     "MessageTextContent",
     "MessageToolCallContent",
     "MessageToolResultContent",
diff --git a/python/beeai_framework/backend/chat.py b/python/beeai_framework/backend/chat.py
index 972b5246..a1ed0ca3 100644
--- a/python/beeai_framework/backend/chat.py
+++ b/python/beeai_framework/backend/chat.py
@@ -229,6 +229,11 @@ class ChatModelOptions(RunnableOptions, total=False):
     Generated chunks will be streamed without validation of the produced tool calls.
     """
 
+    reasoning_effort: str | None
+    """
+    Controls the amount of reasoning effort for models that support it (e.g., "low", "medium", "high").
+    """
+
     fallback_tool: AnyTool | None
     """
     Tool to invoke when the model makes a malformed tool call (for example, when it forgets the name of a tool).
diff --git a/python/beeai_framework/backend/message.py b/python/beeai_framework/backend/message.py
index 3877d35b..befd7e9e 100644
--- a/python/beeai_framework/backend/message.py
+++ b/python/beeai_framework/backend/message.py
@@ -86,6 +86,11 @@ class MessageToolResultContent(BaseModel):
     tool_call_id: str
 
 
+class MessageReasoningContent(BaseModel):
+    type: Literal["reasoning"] = "reasoning"
+    text: str
+
+
 class MessageToolCallContent(BaseModel):
     type: Literal["tool-call"] = "tool-call"
     id: str
@@ -157,7 +162,7 @@ class Message(ABC, Generic[T]):
         return type(self)([c.model_copy() for c in self.content], self.meta.copy())
 
 
-AssistantMessageContent = MessageTextContent | MessageToolCallContent
+AssistantMessageContent = MessageTextContent | MessageToolCallContent | MessageReasoningContent
 
 
 class AssistantMessage(Message[AssistantMessageContent]):
@@ -175,8 +180,10 @@ class AssistantMessage(Message[AssistantMessageContent]):
                 (
                     MessageTextContent(text=c)
                     if isinstance(c, str)
-                    # pyrefly: ignore [bad-argument-type]
-                    else to_any_model([MessageToolCallContent, MessageTextContent], cast(AssistantMessageContent, c))
+                    else to_any_model(
+                        [MessageToolCallContent, MessageReasoningContent, MessageTextContent],
+                        cast(AssistantMessageContent, c),  # pyrefly: ignore [bad-argument-type]
+                    )
                 )
                 for c in cast_list(content)
             ]
@@ -189,12 +196,19 @@ class AssistantMessage(Message[AssistantMessageContent]):
             id=id,
         )
 
+    @property
+    def reasoning(self) -> str:
+        return "".join([x.text for x in self.get_reasoning_messages()])
+
     def get_tool_calls(self) -> list[MessageToolCallContent]:
         return [cont for cont in self.content if isinstance(cont, MessageToolCallContent)]
 
     def get_text_messages(self) -> list[MessageTextContent]:
         return [cont for cont in self.content if isinstance(cont, MessageTextContent)]
 
+    def get_reasoning_messages(self) -> list[MessageReasoningContent]:
+        return [cont for cont in self.content if isinstance(cont, MessageReasoningContent)]
+
 
 class ToolMessage(Message[MessageToolResultContent]):
     role = Role.TOOL
diff --git a/python/beeai_framework/backend/types.py b/python/beeai_framework/backend/types.py
index b44a0a19..222d60a7 100644
--- a/python/beeai_framework/backend/types.py
+++ b/python/beeai_framework/backend/types.py
@@ -33,6 +33,7 @@ class ChatModelParameters(BaseModel):
     seed: int | None = None
     stop_sequences: list[str] | None = None
     stream: bool | None = None
+    reasoning_effort: str | None = None
 
 
 class ChatModelStructureInput(ChatModelParameters, Generic[T]):
@@ -218,6 +219,9 @@ class ChatModelOutput(RunnableOutput):
     def get_text_content(self) -> str:
         return "".join([x.text for x in list(filter(lambda x: isinstance(x, AssistantMessage), self.output))])
 
+    def get_reasoning_content(self) -> str:
+        return "".join([x.reasoning for x in self.output if isinstance(x, AssistantMessage)])
+
 
 ChatModelCache = BaseCache[list[ChatModelOutput]]