🔥New ollama model qwen3:8b 🔥

General
7

FYI Crewai Community

There is a :bug: bug with Qwen3

here is the information

Bug Report: IndexError in litellm when CrewAI Agent with Tools uses Ollama/Qwen

Affected Libraries: crewai, litellm
LLM Provider: Ollama
Model: qwen3:4b (or specific Qwen 1.5 variant used)

Description:

When using CrewAI with an agent configured to use an Ollama model (specifically tested with qwen3) via litellm, an IndexError: list index out of range occurs within litellm’s Ollama prompt templating logic. This error specifically happens during the LLM call that follows a successful tool execution by the agent. If the agent does not have tools assigned, the error does not occur.

The error originates in litellm/litellm_core_utils/prompt_templates/factory.py when attempting to access messages[msg_i].get("tool_calls"), suggesting an incompatibility in how the message history (including the tool call and its result/observation) is structured or processed for Ollama after a tool run.

Steps to Reproduce:

  1. Set up CrewAI to use an Ollama model (e.g., qwen3) as the LLM provider via litellm.
  2. Define a CrewAI Agent and assign one or more tools (e.g., DuckDuckGoSearchTool) to it using the tools=[...] parameter.
  3. Define a Task for this agent that requires it to use one of the assigned tools.
  4. Execute the task using crew.kickoff() (or within a CrewAI Flow).
  5. Observe the agent successfully executing the tool.
  6. Observe the subsequent attempt by CrewAI/litellm to make the next LLM call to Ollama (to process the tool results).

Expected Behavior:

The agent should successfully process the tool’s output and continue its execution by making the next LLM call without errors.

Actual Behavior:

The script crashes during the LLM call after the tool execution. An IndexError: list index out of range occurs within litellm, wrapped in a litellm.exceptions.APIConnectionError. The Crew/Task fails.

Error Logs / Traceback:

# Include the relevant traceback here, like the one provided:
Traceback (most recent call last):
  File "C:\Users\mattv\AppData\Local\Programs\Python\Python312\Lib\site-packages\litellm\main.py", line 2870, in completion
    response = base_llm_http_handler.completion(
               ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "C:\Users\mattv\AppData\Local\Programs\Python\Python312\Lib\site-packages\litellm\llms\custom_httpx\llm_http_handler.py", line 269, in completion
    data = provider_config.transform_request(
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "C:\Users\mattv\AppData\Local\Programs\Python\Python312\Lib\site-packages\litellm\llms\ollama\completion\transformation.py", line 322, in transform_request
    modified_prompt = ollama_pt(model=model, messages=messages)
                      ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "C:\Users\mattv\AppData\Local\Programs\Python\Python312\Lib\site-packages\litellm\litellm_core_utils\prompt_templates\factory.py", line 229, in ollama_pt
    tool_calls = messages[msg_i].get("tool_calls")
                 ~~~~~~~~^^^^^^^
IndexError: list index out of range

# Potentially include the higher-level CrewAI traceback as well if helpful

Environment:

  • Python Version: [3.12.9]
  • crewai Version: [0.118.0]
  • crewai-tools Version: [0.43.0]
  • litellm Version: [1.67.1]
  • Ollama Version: [6.4.0]
  • LLM Model: [qwen3:8b, qwen3:4b. qwen3:14b]
  • Operating System: [Windows 11 Version 24H2 (0S Build 26120.3941)]

Workaround:

Commenting out or removing the tools=[...] list from the Agent’s definition prevents this specific IndexError.
The agent can then make LLM calls via Ollama/`litellm

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