fix: Implement Ollama sequential tool calling fix

Modified conversation format for Ollama to handle tool results properly:
- Assistant messages no longer include 'tool_calls' field for Ollama
- Tool results are passed as user messages with natural language format
- Prevents infinite loop of repeated tool calls

This allows Ollama to properly execute sequential tool calls as intended.

Fixes #854

Co-authored-by: Mervin Praison <MervinPraison@users.noreply.github.com>

Author: claude[bot]

src/praisonai-agents/praisonaiagents/llm/llm.py

@@ -812,11 +812,20 @@ def get_response(
                     if tool_calls and execute_tool_fn:
                         # Convert tool_calls to a serializable format for all providers
                         serializable_tool_calls = self._serialize_tool_calls(tool_calls)
-                        messages.append({
-                            "role": "assistant",
-                            "content": response_text,
-                            "tool_calls": serializable_tool_calls
-                        })
+                        # Check if this is Ollama provider
+                        if self._is_ollama_provider():
+                            # For Ollama, only include role and content
+                            messages.append({
+                                "role": "assistant",
+                                "content": response_text
+                            })
+                        else:
+                            # For other providers, include tool_calls
+                            messages.append({
+                                "role": "assistant",
+                                "content": response_text,
+                                "tool_calls": serializable_tool_calls
+                            })
 
                         should_continue = False
                         tool_results = []  # Store all tool results
@@ -842,11 +851,21 @@ def get_response(
                                 logging.debug(f"[TOOL_EXEC_DEBUG] About to display tool call with message: {display_message}")
                                 display_tool_call(display_message, console=console)
 
-                            messages.append({
-                                "role": "tool",
-                                "tool_call_id": tool_call_id,
-                                "content": json.dumps(tool_result) if tool_result is not None else "Function returned an empty output"
-                            })
+                            # Check if this is Ollama provider
+                            if self._is_ollama_provider():
+                                # For Ollama, use user role and format as natural language
+                                tool_result_content = json.dumps(tool_result) if tool_result is not None else "an empty output"
+                                messages.append({
+                                    "role": "user",
+                                    "content": f"The {function_name} function returned: {tool_result_content}"
+                                })
+                            else:
+                                # For other providers, use tool role with tool_call_id
+                                messages.append({
+                                    "role": "tool",
+                                    "tool_call_id": tool_call_id,
+                                    "content": json.dumps(tool_result) if tool_result is not None else "Function returned an empty output"
+                                })
 
                             # Check if we should continue (for tools like sequential thinking)
                             # This mimics the logic from agent.py lines 1004-1007
@@ -1303,11 +1322,20 @@ async def get_response_async(
                 if tools and execute_tool_fn and tool_calls:
                     # Convert tool_calls to a serializable format for all providers
                     serializable_tool_calls = self._serialize_tool_calls(tool_calls)
-                    messages.append({
-                        "role": "assistant",
-                        "content": response_text,
-                        "tool_calls": serializable_tool_calls
-                    })
+                    # Check if it's Ollama provider
+                    if self._is_ollama_provider():
+                        # For Ollama, only include role and content
+                        messages.append({
+                            "role": "assistant",
+                            "content": response_text
+                        })
+                    else:
+                        # For other providers, include tool_calls
+                        messages.append({
+                            "role": "assistant",
+                            "content": response_text,
+                            "tool_calls": serializable_tool_calls
+                        })
 
                     tool_results = []  # Store all tool results
                     for tool_call in tool_calls:
@@ -1325,11 +1353,21 @@ async def get_response_async(
                             else:
                                 display_message += "Function returned no output"
                             display_tool_call(display_message, console=console)
-                        messages.append({
-                            "role": "tool",
-                            "tool_call_id": tool_call_id,
-                            "content": json.dumps(tool_result) if tool_result is not None else "Function returned an empty output"
-                        })
+                        # Check if it's Ollama provider
+                        if self._is_ollama_provider():
+                            # For Ollama, use user role and natural language format
+                            content = f"The {function_name} function returned: {json.dumps(tool_result) if tool_result is not None else 'an empty output'}"
+                            messages.append({
+                                "role": "user",
+                                "content": content
+                            })
+                        else:
+                            # For other providers, use tool role with tool_call_id
+                            messages.append({
+                                "role": "tool",
+                                "tool_call_id": tool_call_id,
+                                "content": json.dumps(tool_result) if tool_result is not None else "Function returned an empty output"
+                            })
 
                     # Get response after tool calls
                     response_text = ""