feat: add support for streaming tool call events

lib/crewai/src/crewai/llms/base_llm.py

@@ -354,8 +354,17 @@ class BaseLLM(ABC):
         from_task: Task | None = None,
         from_agent: Agent | None = None,
         tool_call: dict[str, Any] | None = None,
+        call_type: LLMCallType | None = None,
     ) -> None:
-        """Emit stream chunk event."""
+        """Emit stream chunk event.
+
+        Args:
+            chunk: The text content of the chunk.
+            from_task: The task that initiated the call.
+            from_agent: The agent that initiated the call.
+            tool_call: Tool call information if this is a tool call chunk.
+            call_type: The type of LLM call (LLM_CALL or TOOL_CALL).
+        """
         if not hasattr(crewai_event_bus, "emit"):
             raise ValueError("crewai_event_bus does not have an emit method") from None
 
@@ -366,6 +375,7 @@ class BaseLLM(ABC):
                 tool_call=tool_call,
                 from_task=from_task,
                 from_agent=from_agent,
+                call_type=call_type,
             ),
         )
 

lib/crewai/src/crewai/llms/providers/anthropic/completion.py

@@ -598,6 +598,8 @@ class AnthropicCompletion(BaseLLM):
         # (the SDK sets it internally)
         stream_params = {k: v for k, v in params.items() if k != "stream"}
 
+        current_tool_calls: dict[int, dict[str, Any]] = {}
+
         # Make streaming API call
         with self.client.messages.stream(**stream_params) as stream:
             for event in stream:
@@ -610,6 +612,55 @@ class AnthropicCompletion(BaseLLM):
                         from_agent=from_agent,
                     )
 
+                if event.type == "content_block_start":
+                    block = event.content_block
+                    if block.type == "tool_use":
+                        block_index = event.index
+                        current_tool_calls[block_index] = {
+                            "id": block.id,
+                            "name": block.name,
+                            "arguments": "",
+                            "index": block_index,
+                        }
+                        self._emit_stream_chunk_event(
+                            chunk="",
+                            from_task=from_task,
+                            from_agent=from_agent,
+                            tool_call={
+                                "id": block.id,
+                                "function": {
+                                    "name": block.name,
+                                    "arguments": "",
+                                },
+                                "type": "function",
+                                "index": block_index,
+                            },
+                            call_type=LLMCallType.TOOL_CALL,
+                        )
+                elif event.type == "content_block_delta":
+                    if event.delta.type == "input_json_delta":
+                        block_index = event.index
+                        partial_json = event.delta.partial_json
+                        if block_index in current_tool_calls and partial_json:
+                            current_tool_calls[block_index]["arguments"] += partial_json
+                            self._emit_stream_chunk_event(
+                                chunk=partial_json,
+                                from_task=from_task,
+                                from_agent=from_agent,
+                                tool_call={
+                                    "id": current_tool_calls[block_index]["id"],
+                                    "function": {
+                                        "name": current_tool_calls[block_index]["name"],
+                                        "arguments": current_tool_calls[block_index][
+                                            "arguments"
+                                        ],
+                                    },
+                                    "type": "function",
+                                    "index": block_index,
+                                },
+                                call_type=LLMCallType.TOOL_CALL,
+                            )
+
             final_message: Message = stream.get_final_message()
 
         thinking_blocks: list[ThinkingBlock] = []
@@ -941,6 +992,8 @@ class AnthropicCompletion(BaseLLM):
 
         stream_params = {k: v for k, v in params.items() if k != "stream"}
 
+        current_tool_calls: dict[int, dict[str, Any]] = {}
+
         async with self.async_client.messages.stream(**stream_params) as stream:
             async for event in stream:
                 if hasattr(event, "delta") and hasattr(event.delta, "text"):
@@ -952,6 +1005,55 @@ class AnthropicCompletion(BaseLLM):
                         from_agent=from_agent,
                     )
 
+                if event.type == "content_block_start":
+                    block = event.content_block
+                    if block.type == "tool_use":
+                        block_index = event.index
+                        current_tool_calls[block_index] = {
+                            "id": block.id,
+                            "name": block.name,
+                            "arguments": "",
+                            "index": block_index,
+                        }
+                        self._emit_stream_chunk_event(
+                            chunk="",
+                            from_task=from_task,
+                            from_agent=from_agent,
+                            tool_call={
+                                "id": block.id,
+                                "function": {
+                                    "name": block.name,
+                                    "arguments": "",
+                                },
+                                "type": "function",
+                                "index": block_index,
+                            },
+                            call_type=LLMCallType.TOOL_CALL,
+                        )
+                elif event.type == "content_block_delta":
+                    if event.delta.type == "input_json_delta":
+                        block_index = event.index
+                        partial_json = event.delta.partial_json
+                        if block_index in current_tool_calls and partial_json:
+                            current_tool_calls[block_index]["arguments"] += partial_json
+                            self._emit_stream_chunk_event(
+                                chunk=partial_json,
+                                from_task=from_task,
+                                from_agent=from_agent,
+                                tool_call={
+                                    "id": current_tool_calls[block_index]["id"],
+                                    "function": {
+                                        "name": current_tool_calls[block_index]["name"],
+                                        "arguments": current_tool_calls[block_index][
+                                            "arguments"
+                                        ],
+                                    },
+                                    "type": "function",
+                                    "index": block_index,
+                                },
+                                call_type=LLMCallType.TOOL_CALL,
+                            )
+
             final_message: Message = await stream.get_final_message()
 
         usage = self._extract_anthropic_token_usage(final_message)

lib/crewai/src/crewai/llms/providers/azure/completion.py

@@ -674,7 +674,7 @@ class AzureCompletion(BaseLLM):
         self,
         update: StreamingChatCompletionsUpdate,
         full_response: str,
-        tool_calls: dict[str, dict[str, str]],
+        tool_calls: dict[str, dict[str, Any]],
         from_task: Any | None = None,
         from_agent: Any | None = None,
     ) -> str:
@@ -702,12 +702,13 @@ class AzureCompletion(BaseLLM):
                 )
 
             if choice.delta and choice.delta.tool_calls:
-                for tool_call in choice.delta.tool_calls:
+                for idx, tool_call in enumerate(choice.delta.tool_calls):
                     call_id = tool_call.id or "default"
                     if call_id not in tool_calls:
                         tool_calls[call_id] = {
                             "name": "",
                             "arguments": "",
+                            "index": idx,
                         }
 
                     if tool_call.function and tool_call.function.name:
@@ -715,12 +716,30 @@ class AzureCompletion(BaseLLM):
                     if tool_call.function and tool_call.function.arguments:
                         tool_calls[call_id]["arguments"] += tool_call.function.arguments
 
+                    self._emit_stream_chunk_event(
+                        chunk=tool_call.function.arguments
+                        if tool_call.function and tool_call.function.arguments
+                        else "",
+                        from_task=from_task,
+                        from_agent=from_agent,
+                        tool_call={
+                            "id": call_id,
+                            "function": {
+                                "name": tool_calls[call_id]["name"],
+                                "arguments": tool_calls[call_id]["arguments"],
+                            },
+                            "type": "function",
+                            "index": tool_calls[call_id]["index"],
+                        },
+                        call_type=LLMCallType.TOOL_CALL,
+                    )
+
         return full_response
 
     def _finalize_streaming_response(
         self,
         full_response: str,
-        tool_calls: dict[str, dict[str, str]],
+        tool_calls: dict[str, dict[str, Any]],
         usage_data: dict[str, int],
         params: AzureCompletionParams,
         available_functions: dict[str, Any] | None = None,

lib/crewai/src/crewai/llms/providers/bedrock/completion.py

@@ -315,9 +315,7 @@ class BedrockCompletion(BaseLLM):
                 messages
             )
 
-            if not self._invoke_before_llm_call_hooks(
+            if not self._invoke_before_llm_call_hooks(formatted_messages, from_agent):
-                cast(list[LLMMessage], formatted_messages), from_agent
-            ):
                 raise ValueError("LLM call blocked by before_llm_call hook")
 
             # Prepare request body
@@ -361,7 +359,7 @@ class BedrockCompletion(BaseLLM):
 
             if self.stream:
                 return self._handle_streaming_converse(
-                    cast(list[LLMMessage], formatted_messages),
+                    formatted_messages,
                     body,
                     available_functions,
                     from_task,
@@ -369,7 +367,7 @@ class BedrockCompletion(BaseLLM):
                 )
 
             return self._handle_converse(
-                cast(list[LLMMessage], formatted_messages),
+                formatted_messages,
                 body,
                 available_functions,
                 from_task,
@@ -433,7 +431,7 @@ class BedrockCompletion(BaseLLM):
             )
 
             formatted_messages, system_message = self._format_messages_for_converse(
-                messages  # type: ignore[arg-type]
+                messages
             )
 
             body: BedrockConverseRequestBody = {
@@ -687,8 +685,10 @@ class BedrockCompletion(BaseLLM):
     ) -> str:
         """Handle streaming converse API call with comprehensive event handling."""
         full_response = ""
-        current_tool_use = None
+        current_tool_use: dict[str, Any] | None = None
-        tool_use_id = None
+        tool_use_id: str | None = None
+        tool_use_index = 0
+        accumulated_tool_input = ""
 
         try:
             response = self.client.converse_stream(
@@ -709,9 +709,30 @@ class BedrockCompletion(BaseLLM):
 
                     elif "contentBlockStart" in event:
                         start = event["contentBlockStart"].get("start", {})
+                        content_block_index = event["contentBlockStart"].get(
+                            "contentBlockIndex", 0
+                        )
                         if "toolUse" in start:
-                            current_tool_use = start["toolUse"]
+                            tool_use_block = start["toolUse"]
+                            current_tool_use = cast(dict[str, Any], tool_use_block)
                             tool_use_id = current_tool_use.get("toolUseId")
+                            tool_use_index = content_block_index
+                            accumulated_tool_input = ""
+                            self._emit_stream_chunk_event(
+                                chunk="",
+                                from_task=from_task,
+                                from_agent=from_agent,
+                                tool_call={
+                                    "id": tool_use_id or "",
+                                    "function": {
+                                        "name": current_tool_use.get("name", ""),
+                                        "arguments": "",
+                                    },
+                                    "type": "function",
+                                    "index": tool_use_index,
+                                },
+                                call_type=LLMCallType.TOOL_CALL,
+                            )
                         logging.debug(
                             f"Tool use started in stream: {json.dumps(current_tool_use)} (ID: {tool_use_id})"
                         )
@@ -730,7 +751,23 @@ class BedrockCompletion(BaseLLM):
                         elif "toolUse" in delta and current_tool_use:
                             tool_input = delta["toolUse"].get("input", "")
                             if tool_input:
+                                accumulated_tool_input += tool_input
                                 logging.debug(f"Tool input delta: {tool_input}")
+                                self._emit_stream_chunk_event(
+                                    chunk=tool_input,
+                                    from_task=from_task,
+                                    from_agent=from_agent,
+                                    tool_call={
+                                        "id": tool_use_id or "",
+                                        "function": {
+                                            "name": current_tool_use.get("name", ""),
+                                            "arguments": accumulated_tool_input,
+                                        },
+                                        "type": "function",
+                                        "index": tool_use_index,
+                                    },
+                                    call_type=LLMCallType.TOOL_CALL,
+                                )
                     elif "contentBlockStop" in event:
                         logging.debug("Content block stopped in stream")
                         if current_tool_use and available_functions:
@@ -848,7 +885,7 @@ class BedrockCompletion(BaseLLM):
 
     async def _ahandle_converse(
         self,
-        messages: list[dict[str, Any]],
+        messages: list[LLMMessage],
         body: BedrockConverseRequestBody,
         available_functions: Mapping[str, Any] | None = None,
         from_task: Any | None = None,
@@ -1013,7 +1050,7 @@ class BedrockCompletion(BaseLLM):
 
     async def _ahandle_streaming_converse(
         self,
-        messages: list[dict[str, Any]],
+        messages: list[LLMMessage],
         body: BedrockConverseRequestBody,
         available_functions: dict[str, Any] | None = None,
         from_task: Any | None = None,
@@ -1021,8 +1058,10 @@ class BedrockCompletion(BaseLLM):
     ) -> str:
         """Handle async streaming converse API call."""
         full_response = ""
-        current_tool_use = None
+        current_tool_use: dict[str, Any] | None = None
-        tool_use_id = None
+        tool_use_id: str | None = None
+        tool_use_index = 0
+        accumulated_tool_input = ""
 
         try:
             async_client = await self._ensure_async_client()
@@ -1044,9 +1083,30 @@ class BedrockCompletion(BaseLLM):
 
                     elif "contentBlockStart" in event:
                         start = event["contentBlockStart"].get("start", {})
+                        content_block_index = event["contentBlockStart"].get(
+                            "contentBlockIndex", 0
+                        )
                         if "toolUse" in start:
-                            current_tool_use = start["toolUse"]
+                            tool_use_block = start["toolUse"]
+                            current_tool_use = cast(dict[str, Any], tool_use_block)
                             tool_use_id = current_tool_use.get("toolUseId")
+                            tool_use_index = content_block_index
+                            accumulated_tool_input = ""
+                            self._emit_stream_chunk_event(
+                                chunk="",
+                                from_task=from_task,
+                                from_agent=from_agent,
+                                tool_call={
+                                    "id": tool_use_id or "",
+                                    "function": {
+                                        "name": current_tool_use.get("name", ""),
+                                        "arguments": "",
+                                    },
+                                    "type": "function",
+                                    "index": tool_use_index,
+                                },
+                                call_type=LLMCallType.TOOL_CALL,
+                            )
                             logging.debug(
                                 f"Tool use started in stream: {current_tool_use.get('name')} (ID: {tool_use_id})"
                             )
@@ -1065,7 +1125,23 @@ class BedrockCompletion(BaseLLM):
                         elif "toolUse" in delta and current_tool_use:
                             tool_input = delta["toolUse"].get("input", "")
                             if tool_input:
+                                accumulated_tool_input += tool_input
                                 logging.debug(f"Tool input delta: {tool_input}")
+                                self._emit_stream_chunk_event(
+                                    chunk=tool_input,
+                                    from_task=from_task,
+                                    from_agent=from_agent,
+                                    tool_call={
+                                        "id": tool_use_id or "",
+                                        "function": {
+                                            "name": current_tool_use.get("name", ""),
+                                            "arguments": accumulated_tool_input,
+                                        },
+                                        "type": "function",
+                                        "index": tool_use_index,
+                                    },
+                                    call_type=LLMCallType.TOOL_CALL,
+                                )
 
                     elif "contentBlockStop" in event:
                         logging.debug("Content block stopped in stream")
@@ -1174,7 +1250,7 @@ class BedrockCompletion(BaseLLM):
 
     def _format_messages_for_converse(
         self, messages: str | list[LLMMessage]
-    ) -> tuple[list[dict[str, Any]], str | None]:
+    ) -> tuple[list[LLMMessage], str | None]:
         """Format messages for Converse API following AWS documentation.
 
         Note: Returns dict[str, Any] instead of LLMMessage because Bedrock uses
@@ -1184,7 +1260,7 @@ class BedrockCompletion(BaseLLM):
         # Use base class formatting first
         formatted_messages = self._format_messages(messages)
 
-        converse_messages: list[dict[str, Any]] = []
+        converse_messages: list[LLMMessage] = []
         system_message: str | None = None
 
         for message in formatted_messages:

lib/crewai/src/crewai/llms/providers/gemini/completion.py

@@ -1,5 +1,6 @@
 from __future__ import annotations
 
+import json
 import logging
 import os
 import re
@@ -677,17 +678,39 @@ class GeminiCompletion(BaseLLM):
         if chunk.candidates:
             candidate = chunk.candidates[0]
             if candidate.content and candidate.content.parts:
-                for part in candidate.content.parts:
+                for idx, part in enumerate(candidate.content.parts):
                     if hasattr(part, "function_call") and part.function_call:
                         call_id = part.function_call.name or "default"
+                        args_dict = (
+                            dict(part.function_call.args)
+                            if part.function_call.args
+                            else {}
+                        )
+                        args_json = json.dumps(args_dict)
+
                         if call_id not in function_calls:
                             function_calls[call_id] = {
                                 "name": part.function_call.name,
-                                "args": dict(part.function_call.args)
+                                "args": args_dict,
-                                if part.function_call.args
+                                "index": idx,
-                                else {},
                             }
 
+                        self._emit_stream_chunk_event(
+                            chunk=args_json,
+                            from_task=from_task,
+                            from_agent=from_agent,
+                            tool_call={
+                                "id": call_id,
+                                "function": {
+                                    "name": part.function_call.name or "",
+                                    "arguments": args_json,
+                                },
+                                "type": "function",
+                                "index": function_calls[call_id]["index"],
+                            },
+                            call_type=LLMCallType.TOOL_CALL,
+                        )
+
         return full_response, function_calls, usage_data
 
     def _finalize_streaming_response(

lib/crewai/src/crewai/llms/providers/openai/completion.py

@@ -521,7 +521,7 @@ class OpenAICompletion(BaseLLM):
     ) -> str:
         """Handle streaming chat completion."""
         full_response = ""
-        tool_calls = {}
+        tool_calls: dict[str, dict[str, Any]] = {}
 
         if response_model:
             parse_params = {
@@ -592,10 +592,12 @@ class OpenAICompletion(BaseLLM):
             if chunk_delta.tool_calls:
                 for tool_call in chunk_delta.tool_calls:
                     call_id = tool_call.id or "default"
+                    tool_index = tool_call.index if tool_call.index is not None else 0
                     if call_id not in tool_calls:
                         tool_calls[call_id] = {
                             "name": "",
                             "arguments": "",
+                            "index": tool_index,
                         }
 
                     if tool_call.function and tool_call.function.name:
@@ -603,6 +605,24 @@ class OpenAICompletion(BaseLLM):
                     if tool_call.function and tool_call.function.arguments:
                         tool_calls[call_id]["arguments"] += tool_call.function.arguments
 
+                    self._emit_stream_chunk_event(
+                        chunk=tool_call.function.arguments
+                        if tool_call.function and tool_call.function.arguments
+                        else "",
+                        from_task=from_task,
+                        from_agent=from_agent,
+                        tool_call={
+                            "id": call_id,
+                            "function": {
+                                "name": tool_calls[call_id]["name"],
+                                "arguments": tool_calls[call_id]["arguments"],
+                            },
+                            "type": "function",
+                            "index": tool_calls[call_id]["index"],
+                        },
+                        call_type=LLMCallType.TOOL_CALL,
+                    )
+
         self._track_token_usage_internal(usage_data)
 
         if tool_calls and available_functions:
@@ -789,7 +809,7 @@ class OpenAICompletion(BaseLLM):
     ) -> str:
         """Handle async streaming chat completion."""
         full_response = ""
-        tool_calls = {}
+        tool_calls: dict[str, dict[str, Any]] = {}
 
         if response_model:
             completion_stream: AsyncIterator[
@@ -871,10 +891,12 @@ class OpenAICompletion(BaseLLM):
             if chunk_delta.tool_calls:
                 for tool_call in chunk_delta.tool_calls:
                     call_id = tool_call.id or "default"
+                    tool_index = tool_call.index if tool_call.index is not None else 0
                     if call_id not in tool_calls:
                         tool_calls[call_id] = {
                             "name": "",
                             "arguments": "",
+                            "index": tool_index,
                         }
 
                     if tool_call.function and tool_call.function.name:
@@ -882,6 +904,24 @@ class OpenAICompletion(BaseLLM):
                     if tool_call.function and tool_call.function.arguments:
                         tool_calls[call_id]["arguments"] += tool_call.function.arguments
 
+                    self._emit_stream_chunk_event(
+                        chunk=tool_call.function.arguments
+                        if tool_call.function and tool_call.function.arguments
+                        else "",
+                        from_task=from_task,
+                        from_agent=from_agent,
+                        tool_call={
+                            "id": call_id,
+                            "function": {
+                                "name": tool_calls[call_id]["name"],
+                                "arguments": tool_calls[call_id]["arguments"],
+                            },
+                            "type": "function",
+                            "index": tool_calls[call_id]["index"],
+                        },
+                        call_type=LLMCallType.TOOL_CALL,
+                    )
+
         self._track_token_usage_internal(usage_data)
 
         if tool_calls and available_functions: