[BUG] UnicodeDecodeError: 'charmap' codec can't decode byte 0x81 in position 1980

[serkanyasr]

Description

The error appears while trying to load a JSON file inside the litellm dependency.

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✅ There was no problem in crewai v0.117.0.

🚫 After upgrading to v0.117.1, the encoding issue started to occur.

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Additional Info:

• OS: Windows 11
• Python: 3.12.6
• UV version: latest
• CrewAI installed via uv tool install crewai
• Running crewai run triggers a forced environment rebuild and dependency reinstallation.

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Possible Cause:
It seems that during crewai run, litellm package tries to load a file without explicitly setting encoding="utf-8" (default encoding on Windows is cp1254/cp1252, causing crash).

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Expected behavior:

• CrewAI should set the correct encoding when reading files.
• Running crewai run should not crash immediately due to encoding issues.

---

Temporary Workaround:

• Downgrade CrewAI CLI back to v0.117.0
• or manually pin litellm==1.67.1 and patch code to enforce UTF-8 encoding.

---

Steps to Reproduce

Install CrewAI CLI via uv tool install crewai

Make sure you have CrewAI version v0.117.1 (uv tool list to verify).

Create a new project using crewai create crew my_project

Enter the project directory.

Run crewai run

Expected behavior

Observe the crash: UnicodeDecodeError: 'charmap' codec can't decode byte 0x81 in position 1980

Screenshots/Code snippets

PS D:\agent_projects\vocavoice> uv tool list
crewai v0.117.1

• crewai.exe
  PS D:\agent_projects\vocavoice> crewai run
  Running the Crew
  Using CPython 3.12.6 interpreter at: C:\Users\yasar\AppData\Local\Programs\Python\Python312\python.exe
  Creating virtual environment at: .venv
  Built vocavoice @ file:///D:/agent_projects/vocavoice
  ░░░░░░░░░░░░░░░░░░░░ [0/216] Installing wheels... warning: Failed to hardlink files; falling back to full copy. This may lead to degraded performance.
  If the cache and target directories are on different filesystems, hardlinking may not be supported.
  If this is intentional, set export UV_LINK_MODE=copy or use --link-mode=copy to suppress this warning.
  Installed 216 packages in 9.59s
  Traceback (most recent call last):
  File "", line 198, in run_module_as_main
  File "", line 88, in run_code
  File "D:\agent_projects\vocavoice.venv\Scripts\run_crew.exe_main.py", line 4, in
  File "D:\agent_projects\vocavoice\src\vocavoice\main.py", line 10, in
  from vocavoice.crew import Vocavoice
  File "D:\agent_projects\vocavoice\src\vocavoice\crew.py", line 2, in
  from crewai import Agent, Crew, Process, Task
  File "D:\agent_projects\vocavoice.venv\Lib\site-packages\crewai_init.py", line 3, in
  from crewai.agent import Agent
  File "D:\agent_projects\vocavoice.venv\Lib\site-packages\crewai\agent.py", line 9, in
  from crewai.agents.crew_agent_executor import CrewAgentExecutor
  File "D:\agent_projects\vocavoice.venv\Lib\site-packages\crewai\agents\crew_agent_executor.py", line 13, in
  from crewai.llm import BaseLLM
  File "D:\agent_projects\vocavoice.venv\Lib\site-packages\crewai\llm.py", line 24, in
  from litellm.types.utils import ChatCompletionDeltaToolCall
  File "D:\agent_projects\vocavoice.venv\Lib\site-packages\litellm_init_.py", line 762, in
  from .cost_calculator import completion_cost
  File "D:\agent_projects\vocavoice.venv\Lib\site-packages\litellm\cost_calculator.py", line 19, in
  from litellm.litellm_core_utils.llm_cost_calc.utils import (
  File "D:\agent_projects\vocavoice.venv\Lib\site-packages\litellm\litellm_core_utils\llm_cost_calc\utils.py", line 9, in
  from litellm.utils import get_model_info
  File "D:\agent_projects\vocavoice.venv\Lib\site-packages\litellm\utils.py", line 188, in
  json_data = json.load(f)
  ^^^^^^^^^^^^
  File "C:\Users\yasar\AppData\Local\Programs\Python\Python312\Lib\json_init_.py", line 293, in load
  return loads(fp.read(),
  ^^^^^^^^^
  File "C:\Users\yasar\AppData\Local\Programs\Python\Python312\Lib\encodings\cp1254.py", line 23, in decode
  return codecs.charmap_decode(input,self.errors,decoding_table)[0]
  ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  UnicodeDecodeError: 'charmap' codec can't decode byte 0x81 in position 1980: character maps to
  An error occurred while running the crew: Command '['uv', 'run', 'run_crew']' returned non-zero exit status 1.

Operating System

Windows 11

Python Version

3.12

crewAI Version

v0.117.1

crewAI Tools Version

v0.117.1

Virtual Environment

Venv

Evidence

UnicodeDecodeError: 'charmap' codec can't decode byte 0x81 in position 1980: character maps to
An error occurred while running the crew: Command '['uv', 'run', 'run_crew']' returned non-zero exit status 1.

Possible Solution

• Downgrade CrewAI CLI back to v0.117.0
• or manually pin litellm==1.67.1 and patch code to enforce UTF-8 encoding.

Additional context

.

[lucasgomide]

would you mind sharing your crew code?

[lucasgomide]

We upgraded LiteLLM to the latest version on 0.117.1that is probably the issue. However, we need more context to help you address it

[mouramax]

@lucasgomide, the issue seems to be with LiteLLM itself, specifically right here:

try:
    # Requires Python 3.9+
    with resources.files("litellm.litellm_core_utils.tokenizers").joinpath(
        "anthropic_tokenizer.json"
    ).open("r") as f:  # <- Problem: Encoding isn't specified
        json_data = json.load(f)

It's the classic problem of opening a file without specifying the encoding. And the official Python documentation says:

In text mode, if encoding is not specified the encoding used is platform-dependent: locale.getencoding() is called to get the current locale encoding.

The problem doesn't pop up on Linux, for instance, which already defaults to UTF-8, but it does happen on Windows. So, it's something that really needs to be fixed over in LiteLLM.

By the way, a while back, the same kind of encoding issue when opening files was also reported regarding a CrewAI tool, in this thread.

[lucasgomide]

Opened issue at LiteLLM

Someone has addressed a PR for that BerriAI/litellm#10380

[konetiai]

Hi,

I am also facing the same issue while setting up the project using the CLI command crewai create crew creaw_ai_projects

Error message "PS C:\Users\ADMIN\Documents\Projects\CrewAI> crewai create crew creaw_ai_projects
Traceback (most recent call last):
File "", line 198, in run_module_as_main
File "", line 88, in run_code
File "C:\Users\ADMIN.local\bin\crewai.exe_main.py", line 4, in
File "C:\Users\ADMIN\AppData\Roaming\uv\tools\crewai\Lib\site-packages\crewai_init.py", line 3, in
from crewai.agent import Agent
File "C:\Users\ADMIN\AppData\Roaming\uv\tools\crewai\Lib\site-packages\crewai\agent.py", line 9, in
from crewai.agents.crew_agent_executor import CrewAgentExecutor
File "C:\Users\ADMIN\AppData\Roaming\uv\tools\crewai\Lib\site-packages\crewai\agents\crew_agent_executor.py", line 13, in
from crewai.llm import BaseLLM
File "C:\Users\ADMIN\AppData\Roaming\uv\tools\crewai\Lib\site-packages\crewai\llm.py", line 24, in
from litellm.types.utils import ChatCompletionDeltaToolCall
File "C:\Users\ADMIN\AppData\Roaming\uv\tools\crewai\Lib\site-packages\litellm_init_.py", line 762, in
from .cost_calculator import completion_cost
File "C:\Users\ADMIN\AppData\Roaming\uv\tools\crewai\Lib\site-packages\litellm\cost_calculator.py", line 19, in
from litellm.litellm_core_utils.llm_cost_calc.utils import (
File "C:\Users\ADMIN\AppData\Roaming\uv\tools\crewai\Lib\site-packages\litellm\litellm_core_utils\llm_cost_calc\utils.py", line 9, in
from litellm.utils import get_model_info
File "C:\Users\ADMIN\AppData\Roaming\uv\tools\crewai\Lib\site-packages\litellm\utils.py", line 188, in
json_data = json.load(f)
^^^^^^^^^^^^
File "C:\Users\ADMIN\AppData\Local\Programs\Python\Python312\Lib\json_init_.py", line 293, in load
return loads(fp.read(),
^^^^^^^^^
File "C:\Users\ADMIN\AppData\Local\Programs\Python\Python312\Lib\encodings\cp1252.py", line 23, in decode
return codecs.charmap_decode(input,self.errors,decoding_table)[0]
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
UnicodeDecodeError: 'charmap' codec can't decode byte 0x81 in position 1980: character maps to

Regards,
Prakash K

[ynaponte]

Same problem. Had to rollback to 0.114.0. It gave me the error while trying to import from crewai.flow

[GamingDaveUk]

Was following a purchased course on zenva and during the start of the course it had me create a crew..... crewai create crew my_project and I got this error... spent a long time with the courses ai agent trying everything .....no go.
os: windows 11
python 3.11 in an isolated virtual environment.

[zensim]

How can we Downgrade CrewAI CLI back to v0.117.0?
Thanks

[Vidit-Ostwal]

How can we Downgrade CrewAI CLI back to v0.117.0? Thanks

pip install crewai==0.177.0